77748399556 has 81 divisors (see below), whose sum is σ = 148090600749. Its totient is φ = 35708597376.

The previous prime is 77748399527. The next prime is 77748399563. The reversal of 77748399556 is 65599384777.

The square root of 77748399556 is 278834.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 60530760900 + 17217638656 = 246030^2 + 131216^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 559340935 + ... + 559341073.

Almost surely, 2^77748399556 is an apocalyptic number.

77748399556 is the 278834-th square number.

It is an amenable number.

77748399556 is a deficient number, since it is larger than the sum of its proper divisors (70342201193).

77748399556 is a wasteful number, since it uses less digits than its factorization.

77748399556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434 (or 217 counting only the distinct ones).

The product of its digits is 400075200, while the sum is 70.

The spelling of 77748399556 in words is "seventy-seven billion, seven hundred forty-eight million, three hundred ninety-nine thousand, five hundred fifty-six".