661421024624 has 10 divisors (see below), whose sum is σ = 1281503235240. Its totient is φ = 330710512304.

The previous prime is 661421024623. The next prime is 661421024629. The reversal of 661421024624 is 426420124166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661421024623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20669407004 + ... + 20669407035.

It is an arithmetic number, because the mean of its divisors is an integer number (128150323524).

Almost surely, 2^661421024624 is an apocalyptic number.

It is an amenable number.

661421024624 is a deficient number, since it is larger than the sum of its proper divisors (620082210616).

661421024624 is a wasteful number, since it uses less digits than its factorization.

661421024624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41338814047 (or 41338814041 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 38.

The spelling of 661421024624 in words is "six hundred sixty-one billion, four hundred twenty-one million, twenty-four thousand, six hundred twenty-four".