661894328 has 32 divisors (see below), whose sum is σ = 1250726400. Its totient is φ = 328378848.

The previous prime is 661894319. The next prime is 661894339. The reversal of 661894328 is 823498166.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

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 7 ways as a sum of consecutive naturals, for example, 1004063 + ... + 1004721.

It is an arithmetic number, because the mean of its divisors is an integer number (39085200).

Almost surely, 2^661894328 is an apocalyptic number.

It is an amenable number.

661894328 is a deficient number, since it is larger than the sum of its proper divisors (588832072).

661894328 is a wasteful number, since it uses less digits than its factorization.

661894328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1451 (or 1447 counting only the distinct ones).

The product of its digits is 497664, while the sum is 47.

The square root of 661894328 is about 25727.3070491258. The cubic root of 661894328 is about 871.4909599489.

The spelling of 661894328 in words is "six hundred sixty-one million, eight hundred ninety-four thousand, three hundred twenty-eight".