661957208 has 16 divisors (see below), whose sum is σ = 1354003560. Its totient is φ = 300889600.

The previous prime is 661957189. The next prime is 661957217. The reversal of 661957208 is 802759166.

661957208 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3761033 + ... + 3761208.

Almost surely, 2^661957208 is an apocalyptic number.

It is an amenable number.

661957208 is an abundant number, since it is smaller than the sum of its proper divisors (692046352).

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

661957208 is a wasteful number, since it uses less digits than its factorization.

661957208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7522258 (or 7522254 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 661957208 is about 25728.5290679432. The cubic root of 661957208 is about 871.5185563058.

The spelling of 661957208 in words is "six hundred sixty-one million, nine hundred fifty-seven thousand, two hundred eight".