64438919 has 2 divisors, whose sum is σ = 64438920. Its totient is φ = 64438918.

The previous prime is 64438901. The next prime is 64438967. The reversal of 64438919 is 91983446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64438919 - 2²⁰ = 63390343 is a prime.

It is a super-2 number, since 2×64438919² = 8304748563777122, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 64438919.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64432919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32219459 + 32219460.

It is an arithmetic number, because the mean of its divisors is an integer number (32219460).

Almost surely, 2^64438919 is an apocalyptic number.

64438919 is a deficient number, since it is larger than the sum of its proper divisors (1).

64438919 is an equidigital number, since it uses as much as digits as its factorization.

64438919 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 44.

The square root of 64438919 is about 8027.3855644288. The cubic root of 64438919 is about 400.9123321265.

The spelling of 64438919 in words is "sixty-four million, four hundred thirty-eight thousand, nine hundred nineteen".