644110642612 has 12 divisors (see below), whose sum is σ = 1127346640420. Its totient is φ = 322011602496.

The previous prime is 644110642607. The next prime is 644110642613. The reversal of 644110642612 is 216246011446.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 557536995856 + 86573646756 = 746684^2 + 294234^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644110642613) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10896543 + ... + 10955494.

Almost surely, 2^644110642612 is an apocalyptic number.

It is an amenable number.

644110642612 is a deficient number, since it is larger than the sum of its proper divisors (483235997808).

644110642612 is a wasteful number, since it uses less digits than its factorization.

644110642612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21859410 (or 21859408 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 37.

The spelling of 644110642612 in words is "six hundred forty-four billion, one hundred ten million, six hundred forty-two thousand, six hundred twelve".