77990784 has 64 divisors (see below), whose sum is σ = 209744640. Its totient is φ = 25673216.

The previous prime is 77990749. The next prime is 77990797. The reversal of 77990784 is 48709977.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30649 + ... + 33095.

It is an arithmetic number, because the mean of its divisors is an integer number (3277260).

Almost surely, 2^77990784 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 77990784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104872320).

77990784 is an abundant number, since it is smaller than the sum of its proper divisors (131753856).

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

77990784 is a wasteful number, since it uses less digits than its factorization.

77990784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2547 (or 2535 counting only the distinct ones).

The product of its (nonzero) digits is 889056, while the sum is 51.

The square root of 77990784 is about 8831.2390976578. The cubic root of 77990784 is about 427.2490398051.

The spelling of 77990784 in words is "seventy-seven million, nine hundred ninety thousand, seven hundred eighty-four".