77057256521 has 8 divisors (see below), whose sum is σ = 90213373824. Its totient is φ = 64438123680.

The previous prime is 77057256509. The next prime is 77057256547. The reversal of 77057256521 is 12565275077.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 77057256521 - 2²⁶ = 76990147657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77057253521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134245805 + ... + 134246378.

It is an arithmetic number, because the mean of its divisors is an integer number (11276671728).

Almost surely, 2^77057256521 is an apocalyptic number.

It is an amenable number.

77057256521 is a deficient number, since it is larger than the sum of its proper divisors (13156117303).

77057256521 is a wasteful number, since it uses less digits than its factorization.

77057256521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268492231.

The product of its (nonzero) digits is 1029000, while the sum is 47.

The spelling of 77057256521 in words is "seventy-seven billion, fifty-seven million, two hundred fifty-six thousand, five hundred twenty-one".