77705664 has 112 divisors (see below), whose sum is σ = 214579200. Its totient is φ = 24800256.

The previous prime is 77705659. The next prime is 77705669. The reversal of 77705664 is 46650777.

It is an interprime number because it is at equal distance from previous prime (77705659) and next prime (77705669).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77705669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 712842 + ... + 712950.

Almost surely, 2^77705664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77705664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107289600).

77705664 is an abundant number, since it is smaller than the sum of its proper divisors (136873536).

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

77705664 is a wasteful number, since it uses less digits than its factorization.

77705664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 240 counting only the distinct ones).

The product of its (nonzero) digits is 246960, while the sum is 42.

The square root of 77705664 is about 8815.0816218569. The cubic root of 77705664 is about 426.7277560099.

The spelling of 77705664 in words is "seventy-seven million, seven hundred five thousand, six hundred sixty-four".