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7928401 = 13609877
BaseRepresentation
bin11110001111101001010001
3112220210201111
4132033221101
54012202101
6441533321
7124250605
oct36175121
915823644
107928401
1145257a8
1227a4241
131847980
1410a5505
15a69251
hex78fa51

7928401 has 4 divisors (see below), whose sum is σ = 8538292. Its totient is φ = 7318512.

The previous prime is 7928369. The next prime is 7928407. The reversal of 7928401 is 1048297.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1048297 = 4324379.

It can be written as a sum of positive squares in 2 ways, for example, as 3154176 + 4774225 = 1776^2 + 2185^2 .

It is a cyclic number.

It is not a de Polignac number, because 7928401 - 25 = 7928369 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7928407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 304926 + ... + 304951.

It is an arithmetic number, because the mean of its divisors is an integer number (2134573).

Almost surely, 27928401 is an apocalyptic number.

It is an amenable number.

7928401 is a deficient number, since it is larger than the sum of its proper divisors (609891).

7928401 is a wasteful number, since it uses less digits than its factorization.

7928401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 609890.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 7928401 is about 2815.7416429779. The cubic root of 7928401 is about 199.4015527572.

The spelling of 7928401 in words is "seven million, nine hundred twenty-eight thousand, four hundred one".

Divisors: 1 13 609877 7928401