64321257 has 32 divisors (see below), whose sum is σ = 115153920. Its totient is φ = 30841920.

The previous prime is 64321253. The next prime is 64321259. The reversal of 64321257 is 75212346.

It is not a de Polignac number, because 64321257 - 2² = 64321253 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64321253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7707 + ... + 13712.

It is an arithmetic number, because the mean of its divisors is an integer number (3598560).

Almost surely, 2^64321257 is an apocalyptic number.

It is an amenable number.

64321257 is a deficient number, since it is larger than the sum of its proper divisors (50832663).

64321257 is a wasteful number, since it uses less digits than its factorization.

64321257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21453.

The product of its digits is 10080, while the sum is 30.

The square root of 64321257 is about 8020.0534287497. The cubic root of 64321257 is about 400.6681686718.

The spelling of 64321257 in words is "sixty-four million, three hundred twenty-one thousand, two hundred fifty-seven".