77664081285 has 128 divisors (see below), whose sum is σ = 162337996800. Its totient is φ = 34488599040.

The previous prime is 77664081283. The next prime is 77664081317. The reversal of 77664081285 is 58218046677.

It is not a de Polignac number, because 77664081285 - 2¹ = 77664081283 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77664081283) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 9255862 + ... + 9264248.

It is an arithmetic number, because the mean of its divisors is an integer number (1268265600).

Almost surely, 2^77664081285 is an apocalyptic number.

It is an amenable number.

77664081285 is an abundant number, since it is smaller than the sum of its proper divisors (84673915515).

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

77664081285 is a wasteful number, since it uses less digits than its factorization.

77664081285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8688 (or 8682 counting only the distinct ones).

The product of its (nonzero) digits is 4515840, while the sum is 54.

The spelling of 77664081285 in words is "seventy-seven billion, six hundred sixty-four million, eighty-one thousand, two hundred eighty-five".