77909568 has 112 divisors (see below), whose sum is σ = 231184704. Its totient is φ = 22947840.

The previous prime is 77909561. The next prime is 77909569. The reversal of 77909568 is 86590977.

It is a self number, because there is not a number n which added to its sum of digits gives 77909568.

It is not an unprimeable number, because it can be changed into a prime (77909561) 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, 77646 + ... + 78642.

Almost surely, 2^77909568 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 77909568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115592352).

77909568 is an abundant number, since it is smaller than the sum of its proper divisors (153275136).

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

77909568 is a wasteful number, since it uses less digits than its factorization.

77909568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060 (or 1050 counting only the distinct ones).

The product of its (nonzero) digits is 952560, while the sum is 51.

The square root of 77909568 is about 8826.6396777029. The cubic root of 77909568 is about 427.1006824907.

The spelling of 77909568 in words is "seventy-seven million, nine hundred nine thousand, five hundred sixty-eight".