661368804 has 24 divisors (see below), whose sum is σ = 1544204928. Its totient is φ = 220311840.

The previous prime is 661368797. The next prime is 661368823. The reversal of 661368804 is 408863166.

It is a happy number.

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, 1909 + ... + 36419.

It is an arithmetic number, because the mean of its divisors is an integer number (64341872).

Almost surely, 2^661368804 is an apocalyptic number.

It is an amenable number.

661368804 is an abundant number, since it is smaller than the sum of its proper divisors (882836124).

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

661368804 is a wasteful number, since it uses less digits than its factorization.

661368804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36115 (or 36113 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 661368804 is about 25717.0916707158. The cubic root of 661368804 is about 871.2602530927.

The spelling of 661368804 in words is "six hundred sixty-one million, three hundred sixty-eight thousand, eight hundred four".