661839696 has 60 divisors (see below), whose sum is σ = 2116839712. Its totient is φ = 189096768.

The previous prime is 661839679. The next prime is 661839709. The reversal of 661839696 is 696938166.

It is a nude number because it is divisible by every one of its digits.

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 11 ways as a sum of consecutive naturals, for example, 327286 + ... + 329301.

Almost surely, 2^661839696 is an apocalyptic number.

It is an amenable number.

661839696 is an abundant number, since it is smaller than the sum of its proper divisors (1455000016).

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

661839696 is a wasteful number, since it uses less digits than its factorization.

661839696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656608 (or 656599 counting only the distinct ones).

The product of its digits is 2519424, while the sum is 54.

The square root of 661839696 is about 25726.2452759823. The cubic root of 661839696 is about 871.4669820005.

The spelling of 661839696 in words is "six hundred sixty-one million, eight hundred thirty-nine thousand, six hundred ninety-six".