644282809590 has 64 divisors (see below), whose sum is σ = 1768243152384. Its totient is φ = 147175688448.

The previous prime is 644282809561. The next prime is 644282809613. The reversal of 644282809590 is 95908282446.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 644282809590.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 577804 + ... + 1273743.

It is an arithmetic number, because the mean of its divisors is an integer number (27628799256).

Almost surely, 2^644282809590 is an apocalyptic number.

644282809590 is an abundant number, since it is smaller than the sum of its proper divisors (1123960342794).

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

644282809590 is a wasteful number, since it uses less digits than its factorization.

644282809590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1853221.

The product of its (nonzero) digits is 9953280, while the sum is 57.

The spelling of 644282809590 in words is "six hundred forty-four billion, two hundred eighty-two million, eight hundred nine thousand, five hundred ninety".