77457728512 has 44 divisors (see below), whose sum is σ = 156210311916. Its totient is φ = 38386073600.

The previous prime is 77457728501. The next prime is 77457728549. The reversal of 77457728512 is 21582775477.

It can be written as a sum of positive squares in 2 ways, for example, as 12379677696 + 65078050816 = 111264^2 + 255104^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218989 + ... + 450412.

Almost surely, 2^77457728512 is an apocalyptic number.

It is an amenable number.

77457728512 is an abundant number, since it is smaller than the sum of its proper divisors (78752583404).

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

77457728512 is a wasteful number, since it uses less digits than its factorization.

77457728512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669534 (or 669516 counting only the distinct ones).

The product of its digits is 7683200, while the sum is 55.

The spelling of 77457728512 in words is "seventy-seven billion, four hundred fifty-seven million, seven hundred twenty-eight thousand, five hundred twelve".