77427231525 has 36 divisors (see below), whose sum is σ = 158492317152. Its totient is φ = 35395305120.

The previous prime is 77427231509. The next prime is 77427231547. The reversal of 77427231525 is 52513272477.

77427231525 is a `hidden beast` number, since 7 + 74 + 27 + 2 + 31 + 525 = 666.

It is not a de Polignac number, because 77427231525 - 2⁴ = 77427231509 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 24578499 + ... + 24581648.

Almost surely, 2^77427231525 is an apocalyptic number.

77427231525 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

77427231525 is an abundant number, since it is smaller than the sum of its proper divisors (81065085627).

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

77427231525 is a wasteful number, since it uses less digits than its factorization.

77427231525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49160170 (or 49160162 counting only the distinct ones).

The product of its digits is 823200, while the sum is 45.

The spelling of 77427231525 in words is "seventy-seven billion, four hundred twenty-seven million, two hundred thirty-one thousand, five hundred twenty-five".