77921964 has 36 divisors (see below), whose sum is σ = 207338040. Its totient is φ = 24606720.

The previous prime is 77921951. The next prime is 77921981. The reversal of 77921964 is 46912977.

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 56277 + ... + 57644.

It is an arithmetic number, because the mean of its divisors is an integer number (5759390).

Almost surely, 2^77921964 is an apocalyptic number.

It is an amenable number.

77921964 is an abundant number, since it is smaller than the sum of its proper divisors (129416076).

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

77921964 is a wasteful number, since it uses less digits than its factorization.

77921964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113950 (or 113945 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 77921964 is about 8827.3418422535. The cubic root of 77921964 is about 427.1233329363.

The spelling of 77921964 in words is "seventy-seven million, nine hundred twenty-one thousand, nine hundred sixty-four".