664235523 has 18 divisors (see below), whose sum is σ = 1116097164. Its totient is φ = 379562904.

The previous prime is 664235503. The next prime is 664235531. The reversal of 664235523 is 325532466.

664235523 is a `hidden beast` number, since 6 + 642 + 3 + 5 + 5 + 2 + 3 = 666.

It is not a de Polignac number, because 664235523 - 2⁸ = 664235267 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664235503) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 752661 + ... + 753542.

It is an arithmetic number, because the mean of its divisors is an integer number (62005398).

Almost surely, 2^664235523 is an apocalyptic number.

664235523 is a gapful number since it is divisible by the number (63) formed by its first and last digit.

664235523 is a deficient number, since it is larger than the sum of its proper divisors (451861641).

664235523 is a wasteful number, since it uses less digits than its factorization.

664235523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1506223 (or 1506213 counting only the distinct ones).

The product of its digits is 129600, while the sum is 36.

The square root of 664235523 is about 25772.7670807773. The cubic root of 664235523 is about 872.5172714922.

Adding to 664235523 its reverse (325532466), we get a palindrome (989767989).

The spelling of 664235523 in words is "six hundred sixty-four million, two hundred thirty-five thousand, five hundred twenty-three".