Search a number
-
+
78121120 = 25571117373
BaseRepresentation
bin1001010100000…
…00100010100000
312102222222000211
410222000202200
5124444333440
611430223504
71636006240
oct452004240
9172888024
1078121120
1140108610
12221b4b94
131325311c
14a537b20
156cd1eea
hex4a808a0

78121120 has 192 divisors, whose sum is σ = 244290816. Its totient is φ = 22855680.

The previous prime is 78121111. The next prime is 78121123. The reversal of 78121120 is 2112187.

It is a super-2 number, since 2×781211202 = 12205818780108800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 78121091 and 78121100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78121123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 209254 + ... + 209626.

It is an arithmetic number, because the mean of its divisors is an integer number (1272348).

Almost surely, 278121120 is an apocalyptic number.

78121120 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78121120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122145408).

78121120 is an abundant number, since it is smaller than the sum of its proper divisors (166169696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78121120 is a wasteful number, since it uses less digits than its factorization.

78121120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423 (or 415 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 22.

The square root of 78121120 is about 8838.6152761618. The cubic root of 78121120 is about 427.4869095316.

The spelling of 78121120 in words is "seventy-eight million, one hundred twenty-one thousand, one hundred twenty".