644882763123 has 24 divisors (see below), whose sum is σ = 953241626480. Its totient is φ = 419887722240.

The previous prime is 644882763101. The next prime is 644882763137. The reversal of 644882763123 is 321367288446.

644882763123 is a `hidden beast` number, since 6 + 448 + 8 + 2 + 76 + 3 + 123 = 666.

It is not a de Polignac number, because 644882763123 - 2¹³ = 644882754931 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 644882763123.

It is not an unprimeable number, because it can be changed into a prime (644882763163) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4904583 + ... + 5034351.

Almost surely, 2^644882763123 is an apocalyptic number.

644882763123 is a deficient number, since it is larger than the sum of its proper divisors (308358863357).

644882763123 is a wasteful number, since it uses less digits than its factorization.

644882763123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142659 (or 142656 counting only the distinct ones).

The product of its digits is 9289728, while the sum is 54.

The spelling of 644882763123 in words is "six hundred forty-four billion, eight hundred eighty-two million, seven hundred sixty-three thousand, one hundred twenty-three".