77521425 has 24 divisors (see below), whose sum is σ = 134916960. Its totient is φ = 39168000.

The previous prime is 77521417. The next prime is 77521427. The reversal of 77521425 is 52412577.

It is not a de Polignac number, because 77521425 - 2³ = 77521417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77521427) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25776 + ... + 28625.

It is an arithmetic number, because the mean of its divisors is an integer number (5621540).

Almost surely, 2^77521425 is an apocalyptic number.

77521425 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

77521425 is a deficient number, since it is larger than the sum of its proper divisors (57395535).

77521425 is a wasteful number, since it uses less digits than its factorization.

77521425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54433 (or 54428 counting only the distinct ones).

The product of its digits is 19600, while the sum is 33.

The square root of 77521425 is about 8804.6252049704. The cubic root of 77521425 is about 426.3902340134.

The spelling of 77521425 in words is "seventy-seven million, five hundred twenty-one thousand, four hundred twenty-five".