661313414208 has 56 divisors (see below), whose sum is σ = 1767763527712. Its totient is φ = 218165243904.

The previous prime is 661313414191. The next prime is 661313414219. The reversal of 661313414208 is 802414313166.

It is a happy number.

It is a super-2 number, since 2×661313414208² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17735710 + ... + 17772957.

It is an arithmetic number, because the mean of its divisors is an integer number (31567205852).

Almost surely, 2^661313414208 is an apocalyptic number.

It is an amenable number.

661313414208 is an abundant number, since it is smaller than the sum of its proper divisors (1106450113504).

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

661313414208 is a wasteful number, since it uses less digits than its factorization.

661313414208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35508779 (or 35508769 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 39.

The spelling of 661313414208 in words is "six hundred sixty-one billion, three hundred thirteen million, four hundred fourteen thousand, two hundred eight".