77971620 has 48 divisors (see below), whose sum is σ = 218856960. Its totient is φ = 20741376.

The previous prime is 77971613. The next prime is 77971631. The reversal of 77971620 is 2617977.

77971620 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

77971620 is strictly pandigital in base 9.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27384 + ... + 30096.

It is an arithmetic number, because the mean of its divisors is an integer number (4559520).

Almost surely, 2^77971620 is an apocalyptic number.

It is an amenable number.

77971620 is an abundant number, since it is smaller than the sum of its proper divisors (140885340).

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

77971620 is a wasteful number, since it uses less digits than its factorization.

77971620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3204 (or 3202 counting only the distinct ones).

The product of its (nonzero) digits is 37044, while the sum is 39.

The square root of 77971620 is about 8830.1540190418. The cubic root of 77971620 is about 427.2140422028.

The spelling of 77971620 in words is "seventy-seven million, nine hundred seventy-one thousand, six hundred twenty".