390631660 has 12 divisors (see below), whose sum is σ = 820326528. Its totient is φ = 156252656.

The previous prime is 390631643. The next prime is 390631663. The reversal of 390631660 is 66136093.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (390631663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9765772 + ... + 9765811.

It is an arithmetic number, because the mean of its divisors is an integer number (68360544).

Almost surely, 2^390631660 is an apocalyptic number.

It is an amenable number.

390631660 is an abundant number, since it is smaller than the sum of its proper divisors (429694868).

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

390631660 is a wasteful number, since it uses less digits than its factorization.

390631660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19531592 (or 19531590 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 34.

The square root of 390631660 is about 19764.4038614880. The cubic root of 390631660 is about 731.0085889740.

The spelling of 390631660 in words is "three hundred ninety million, six hundred thirty-one thousand, six hundred sixty".