664535251 has 16 divisors (see below), whose sum is σ = 720211968. Its totient is φ = 611344800.

The previous prime is 664535243. The next prime is 664535269. The reversal of 664535251 is 152535466.

It is not a de Polignac number, because 664535251 - 2³ = 664535243 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 664535251.

It is not an unprimeable number, because it can be changed into a prime (644535251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116281 + ... + 121861.

It is an arithmetic number, because the mean of its divisors is an integer number (45013248).

Almost surely, 2^664535251 is an apocalyptic number.

664535251 is a deficient number, since it is larger than the sum of its proper divisors (55676717).

664535251 is a wasteful number, since it uses less digits than its factorization.

664535251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5802.

The product of its digits is 108000, while the sum is 37.

The square root of 664535251 is about 25778.5812449017. The cubic root of 664535251 is about 872.6484892716.

The spelling of 664535251 in words is "six hundred sixty-four million, five hundred thirty-five thousand, two hundred fifty-one".