664686475 has 24 divisors (see below), whose sum is σ = 846945792. Its totient is φ = 517188000.

The previous prime is 664686437. The next prime is 664686479. The reversal of 664686475 is 574686466.

It is not a de Polignac number, because 664686475 - 2⁹ = 664685963 is a prime.

It is a super-2 number, since 2×664686475² = 883616220095851250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664686479) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 281550 + ... + 283900.

It is an arithmetic number, because the mean of its divisors is an integer number (35289408).

Almost surely, 2^664686475 is an apocalyptic number.

664686475 is a deficient number, since it is larger than the sum of its proper divisors (182259317).

664686475 is a wasteful number, since it uses less digits than its factorization.

664686475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2667 (or 2662 counting only the distinct ones).

The product of its digits is 5806080, while the sum is 52.

The square root of 664686475 is about 25781.5142107674. The cubic root of 664686475 is about 872.7146785802.

Subtracting from 664686475 its reverse (574686466), we obtain a palindrome (90000009).

The spelling of 664686475 in words is "six hundred sixty-four million, six hundred eighty-six thousand, four hundred seventy-five".