661536215300 has 18 divisors (see below), whose sum is σ = 1435533587418. Its totient is φ = 264614486080.

The previous prime is 661536215267. The next prime is 661536215371. The reversal of 661536215300 is 3512635166.

It can be written as a sum of positive squares in 3 ways, for example, as 78790244416 + 582745970884 = 280696^2 + 763378^2 .

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 3307680977 + ... + 3307681176.

Almost surely, 2^661536215300 is an apocalyptic number.

It is an amenable number.

661536215300 is an abundant number, since it is smaller than the sum of its proper divisors (773997372118).

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

661536215300 is a wasteful number, since it uses less digits than its factorization.

661536215300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6615362167 (or 6615362160 counting only the distinct ones).

The product of its (nonzero) digits is 97200, while the sum is 38.

The spelling of 661536215300 in words is "six hundred sixty-one billion, five hundred thirty-six million, two hundred fifteen thousand, three hundred".