664125531 has 4 divisors (see below), whose sum is σ = 885500712. Its totient is φ = 442750352.

The previous prime is 664125479. The next prime is 664125533. The reversal of 664125531 is 135521466.

664125531 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 664125531 - 2⁷ = 664125403 is a prime.

It is a super-2 number, since 2×664125531² = 882125441852063922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 664125492 and 664125501.

It is not an unprimeable number, because it can be changed into a prime (664125533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110687586 + ... + 110687591.

It is an arithmetic number, because the mean of its divisors is an integer number (221375178).

Almost surely, 2^664125531 is an apocalyptic number.

664125531 is a deficient number, since it is larger than the sum of its proper divisors (221375181).

664125531 is a wasteful number, since it uses less digits than its factorization.

664125531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221375180.

The product of its digits is 21600, while the sum is 33.

The square root of 664125531 is about 25770.6331121298. The cubic root of 664125531 is about 872.4691082458.

Adding to 664125531 its reverse (135521466), we get a palindrome (799646997).

The spelling of 664125531 in words is "six hundred sixty-four million, one hundred twenty-five thousand, five hundred thirty-one".