77911992 has 48 divisors (see below), whose sum is σ = 213997680. Its totient is φ = 25603200.

The previous prime is 77911987. The next prime is 77911997. The reversal of 77911992 is 29911977.

It is an interprime number because it is at equal distance from previous prime (77911987) and next prime (77911997).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77911997) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2509 + ... + 12732.

It is an arithmetic number, because the mean of its divisors is an integer number (4458285).

Almost surely, 2^77911992 is an apocalyptic number.

77911992 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

77911992 is an abundant number, since it is smaller than the sum of its proper divisors (136085688).

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

77911992 is a wasteful number, since it uses less digits than its factorization.

77911992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15324 (or 15317 counting only the distinct ones).

The product of its digits is 71442, while the sum is 45.

The square root of 77911992 is about 8826.7769882330. The cubic root of 77911992 is about 427.1051119052.

The spelling of 77911992 in words is "seventy-seven million, nine hundred eleven thousand, nine hundred ninety-two".