661039902 has 24 divisors (see below), whose sum is σ = 1433274336. Its totient is φ = 220189536.

The previous prime is 661039879. The next prime is 661039909. The reversal of 661039902 is 209930166.

661039902 is a `hidden beast` number, since 6 + 610 + 39 + 9 + 0 + 2 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661039909) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 14418 + ... + 39114.

It is an arithmetic number, because the mean of its divisors is an integer number (59719764).

Almost surely, 2^661039902 is an apocalyptic number.

661039902 is an abundant number, since it is smaller than the sum of its proper divisors (772234434).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661039902 is a wasteful number, since it uses less digits than its factorization.

661039902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26192 (or 26189 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 661039902 is about 25710.6962566166. The cubic root of 661039902 is about 871.1158017903.

The spelling of 661039902 in words is "six hundred sixty-one million, thirty-nine thousand, nine hundred two".