644107463 has 4 divisors (see below), whose sum is σ = 656260488. Its totient is φ = 631954440.

The previous prime is 644107459. The next prime is 644107483. The reversal of 644107463 is 364701446.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 644107463 - 2² = 644107459 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644107403) 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, 6076433 + ... + 6076538.

It is an arithmetic number, because the mean of its divisors is an integer number (164065122).

Almost surely, 2^644107463 is an apocalyptic number.

644107463 is a deficient number, since it is larger than the sum of its proper divisors (12153025).

644107463 is a wasteful number, since it uses less digits than its factorization.

644107463 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12153024.

The product of its (nonzero) digits is 48384, while the sum is 35.

The square root of 644107463 is about 25379.2723102929. The cubic root of 644107463 is about 863.6135419985.

The spelling of 644107463 in words is "six hundred forty-four million, one hundred seven thousand, four hundred sixty-three".