64220639 has 16 divisors (see below), whose sum is σ = 75072000. Its totient is φ = 53802144.

The previous prime is 64220633. The next prime is 64220647. The reversal of 64220639 is 93602246.

It is a cyclic number.

It is not a de Polignac number, because 64220639 - 2¹² = 64216543 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 (64220633) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69422 + ... + 70340.

It is an arithmetic number, because the mean of its divisors is an integer number (4692000).

Almost surely, 2^64220639 is an apocalyptic number.

64220639 is a deficient number, since it is larger than the sum of its proper divisors (10851361).

64220639 is a wasteful number, since it uses less digits than its factorization.

64220639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1142.

The product of its (nonzero) digits is 15552, while the sum is 32.

The square root of 64220639 is about 8013.7780727944. The cubic root of 64220639 is about 400.4591373639.

The spelling of 64220639 in words is "sixty-four million, two hundred twenty thousand, six hundred thirty-nine".