661504036 has 24 divisors (see below), whose sum is σ = 1200621240. Its totient is φ = 318528000.

The previous prime is 661504031. The next prime is 661504043. The reversal of 661504036 is 630405166.

It can be written as a sum of positive squares in 4 ways, for example, as 368409636 + 293094400 = 19194^2 + 17120^2 .

It is a junction number, because it is equal to n+sod(n) for n = 661503989 and 661504007.

It is not an unprimeable number, because it can be changed into a prime (661504031) 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 7 ways as a sum of consecutive naturals, for example, 39406 + ... + 53626.

It is an arithmetic number, because the mean of its divisors is an integer number (50025885).

Almost surely, 2^661504036 is an apocalyptic number.

It is an amenable number.

661504036 is a deficient number, since it is larger than the sum of its proper divisors (539117204).

661504036 is a wasteful number, since it uses less digits than its factorization.

661504036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14655 (or 14653 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 661504036 is about 25719.7207605370. The cubic root of 661504036 is about 871.3196320838.

The spelling of 661504036 in words is "six hundred sixty-one million, five hundred four thousand, thirty-six".