64438631 has 4 divisors (see below), whose sum is σ = 65495064. Its totient is φ = 63382200.

The previous prime is 64438607. The next prime is 64438637. The reversal of 64438631 is 13683446.

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 64438631 - 2¹⁸ = 64176487 is a prime.

It is a super-2 number, since 2×64438631² = 8304674330308322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64438591 and 64438600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64438637) 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, 528125 + ... + 528246.

It is an arithmetic number, because the mean of its divisors is an integer number (16373766).

Almost surely, 2^64438631 is an apocalyptic number.

64438631 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

64438631 is a deficient number, since it is larger than the sum of its proper divisors (1056433).

64438631 is a wasteful number, since it uses less digits than its factorization.

64438631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056432.

The product of its digits is 41472, while the sum is 35.

The square root of 64438631 is about 8027.3676258161. The cubic root of 64438631 is about 400.9117348533.

The spelling of 64438631 in words is "sixty-four million, four hundred thirty-eight thousand, six hundred thirty-one".