661874994 has 48 divisors (see below), whose sum is σ = 1646779680. Its totient is φ = 190010880.

The previous prime is 661874947. The next prime is 661875043. The reversal of 661874994 is 499478166.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 661874994.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 84207 + ... + 91730.

It is an arithmetic number, because the mean of its divisors is an integer number (34307910).

Almost surely, 2^661874994 is an apocalyptic number.

661874994 is an abundant number, since it is smaller than the sum of its proper divisors (984904686).

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

661874994 is a wasteful number, since it uses less digits than its factorization.

661874994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175975 (or 175972 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 54.

The square root of 661874994 is about 25726.9312977665. The cubic root of 661874994 is about 871.4824744200.

The spelling of 661874994 in words is "six hundred sixty-one million, eight hundred seventy-four thousand, nine hundred ninety-four".