664751321524 has 24 divisors (see below), whose sum is σ = 1170133033608. Its totient is φ = 330427906560.

The previous prime is 664751321503. The next prime is 664751321543. The reversal of 664751321524 is 425123157466.

It can be written as a sum of positive squares in 4 ways, for example, as 407276265124 + 257475056400 = 638182^2 + 507420^2 .

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 10792864 + ... + 10854280.

It is an arithmetic number, because the mean of its divisors is an integer number (48755543067).

Almost surely, 2^664751321524 is an apocalyptic number.

It is an amenable number.

664751321524 is a deficient number, since it is larger than the sum of its proper divisors (505381712084).

664751321524 is a wasteful number, since it uses less digits than its factorization.

664751321524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77235 (or 77233 counting only the distinct ones).

The product of its digits is 1209600, while the sum is 46.

The spelling of 664751321524 in words is "six hundred sixty-four billion, seven hundred fifty-one million, three hundred twenty-one thousand, five hundred twenty-four".