77641920 has 84 divisors (see below), whose sum is σ = 267065760. Its totient is φ = 20703744.

The previous prime is 77641913. The next prime is 77641931. The reversal of 77641920 is 2914677.

It is a happy number.

77641920 is a `hidden beast` number, since 7 + 7 + 641 + 9 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (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, 10600 + ... + 16359.

Almost surely, 2^77641920 is an apocalyptic number.

It is an amenable number.

77641920 is an abundant number, since it is smaller than the sum of its proper divisors (189423840).

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

77641920 is a wasteful number, since it uses less digits than its factorization.

77641920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26982 (or 26969 counting only the distinct ones).

The product of its (nonzero) digits is 21168, while the sum is 36.

The square root of 77641920 is about 8811.4652584006. The cubic root of 77641920 is about 426.6110387546.

The spelling of 77641920 in words is "seventy-seven million, six hundred forty-one thousand, nine hundred twenty".