661344640402116 has 96 divisors (see below), whose sum is σ = 1762263295543296. Its totient is φ = 191077718656000.

The previous prime is 661344640402073. The next prime is 661344640402207. The reversal of 661344640402116 is 611204046443166.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 349271565 + ... + 351159956.

It is an arithmetic number, because the mean of its divisors is an integer number (18356909328576).

Almost surely, 2^{661344640402116} is an apocalyptic number.

661344640402116 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

661344640402116 is an abundant number, since it is smaller than the sum of its proper divisors (1100918655141180).

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

661344640402116 is a wasteful number, since it uses less digits than its factorization.

661344640402116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 700431873 (or 700431871 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 48.

The spelling of 661344640402116 in words is "six hundred sixty-one trillion, three hundred forty-four billion, six hundred forty million, four hundred two thousand, one hundred sixteen".