77056763281 has 9 divisors (see below), whose sum is σ = 77957292091. Its totient is φ = 76166528944.

The previous prime is 77056763279. The next prime is 77056763309. The reversal of 77056763281 is 18236765077.

The square root of 77056763281 is 277591.

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., 14796532881 + 62260230400 = 121641^2 + 249520^2 .

It is not a de Polignac number, because 77056763281 - 2¹ = 77056763279 is a prime.

It is a super-2 number, since 2×77056763281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77056763681) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 24704040 + ... + 24707158.

Almost surely, 2^77056763281 is an apocalyptic number.

77056763281 is the 277591-st square number.

77056763281 is the 138796-th centered octagonal number.

It is an amenable number.

77056763281 is a deficient number, since it is larger than the sum of its proper divisors (900528810).

77056763281 is an frugal number, since it uses more digits than its factorization.

77056763281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6416 (or 3208 counting only the distinct ones).

The product of its (nonzero) digits is 2963520, while the sum is 52.

The spelling of 77056763281 in words is "seventy-seven billion, fifty-six million, seven hundred sixty-three thousand, two hundred eighty-one".