78120072 has 64 divisors (see below), whose sum is σ = 217785600. Its totient is φ = 25945920.

The previous prime is 78120059. The next prime is 78120073. The reversal of 78120072 is 27002187.

It is a super-2 number, since 2×78120072² = 12205491298570368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (78120073) 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 15 ways as a sum of consecutive naturals, for example, 85297 + ... + 86207.

It is an arithmetic number, because the mean of its divisors is an integer number (3402900).

Almost surely, 2^78120072 is an apocalyptic number.

78120072 is a gapful number since it is divisible by the number (72) 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 78120072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108892800).

78120072 is an abundant number, since it is smaller than the sum of its proper divisors (139665528).

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

78120072 is a wasteful number, since it uses less digits than its factorization.

78120072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1323 (or 1313 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 27.

The square root of 78120072 is about 8838.5559906582. Note that the first 3 decimals coincide. The cubic root of 78120072 is about 427.4849979346.

The spelling of 78120072 in words is "seventy-eight million, one hundred twenty thousand, seventy-two".