77056728 has 64 divisors (see below), whose sum is σ = 220834560. Its totient is φ = 21949056.

The previous prime is 77056717. The next prime is 77056729. The reversal of 77056728 is 82765077.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 77056728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77056729) 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, 87426 + ... + 88302.

It is an arithmetic number, because the mean of its divisors is an integer number (3450540).

Almost surely, 2^77056728 is an apocalyptic number.

It is an amenable number.

77056728 is an abundant number, since it is smaller than the sum of its proper divisors (143777832).

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

77056728 is a wasteful number, since it uses less digits than its factorization.

77056728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1416 (or 1412 counting only the distinct ones).

The product of its (nonzero) digits is 164640, while the sum is 42.

The square root of 77056728 is about 8778.1961700568. The cubic root of 77056728 is about 425.5365366722.

The spelling of 77056728 in words is "seventy-seven million, fifty-six thousand, seven hundred twenty-eight".