644058076464 has 80 divisors (see below), whose sum is σ = 2016747527040. Its totient is φ = 195169112640.

The previous prime is 644058076457. The next prime is 644058076469. The reversal of 644058076464 is 464670850446.

It is a happy number.

644058076464 is a `hidden beast` number, since 6 + 440 + 5 + 80 + 7 + 64 + 64 = 666.

644058076464 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 644058076464.

It is not an unprimeable number, because it can be changed into a prime (644058076469) 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, 67762302 + ... + 67771805.

It is an arithmetic number, because the mean of its divisors is an integer number (25209344088).

Almost surely, 2^644058076464 is an apocalyptic number.

It is an amenable number.

644058076464 is an abundant number, since it is smaller than the sum of its proper divisors (1372689450576).

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

644058076464 is a wasteful number, since it uses less digits than its factorization.

644058076464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135534135 (or 135534123 counting only the distinct ones).

The product of its (nonzero) digits is 15482880, while the sum is 54.

The spelling of 644058076464 in words is "six hundred forty-four billion, fifty-eight million, seventy-six thousand, four hundred sixty-four".