77320656 has 140 divisors (see below), whose sum is σ = 256968672. Its totient is φ = 22068288.

The previous prime is 77320637. The next prime is 77320673. The reversal of 77320656 is 65602377.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 77320656.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 81175 + ... + 82121.

Almost surely, 2^77320656 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 77320656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128484336).

77320656 is an abundant number, since it is smaller than the sum of its proper divisors (179648016).

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

77320656 is an equidigital number, since it uses as much as digits as its factorization.

77320656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 980 (or 959 counting only the distinct ones).

The product of its (nonzero) digits is 52920, while the sum is 36.

The square root of 77320656 is about 8793.2164763527. The cubic root of 77320656 is about 426.0218199496.

The spelling of 77320656 in words is "seventy-seven million, three hundred twenty thousand, six hundred fifty-six".