661888641516024 has 64 divisors (see below), whose sum is σ = 1782077542106400. Its totient is φ = 203650082274816.

The previous prime is 661888641516013. The next prime is 661888641516043. The reversal of 661888641516024 is 420615146888166.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33468379 + ... + 49435914.

Almost surely, 2^{661888641516024} is an apocalyptic number.

It is an amenable number.

661888641516024 is an abundant number, since it is smaller than the sum of its proper divisors (1120188900590376).

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

661888641516024 is a wasteful number, since it uses less digits than its factorization.

661888641516024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82929904 (or 82929900 counting only the distinct ones).

The product of its (nonzero) digits is 106168320, while the sum is 66.

The spelling of 661888641516024 in words is "six hundred sixty-one trillion, eight hundred eighty-eight billion, six hundred forty-one million, five hundred sixteen thousand, twenty-four".