661179868 has 12 divisors (see below), whose sum is σ = 1183973560. Its totient is φ = 322901712.

The previous prime is 661179859. The next prime is 661179913. The reversal of 661179868 is 868971166.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1921863 + ... + 1922206.

Almost surely, 2^661179868 is an apocalyptic number.

It is an amenable number.

661179868 is a deficient number, since it is larger than the sum of its proper divisors (522793692).

661179868 is a wasteful number, since it uses less digits than its factorization.

661179868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3844116 (or 3844114 counting only the distinct ones).

The product of its digits is 870912, while the sum is 52.

The square root of 661179868 is about 25713.4180536155. The cubic root of 661179868 is about 871.1772796676.

The spelling of 661179868 in words is "six hundred sixty-one million, one hundred seventy-nine thousand, eight hundred sixty-eight".