390971636 has 12 divisors (see below), whose sum is σ = 746400480. Its totient is φ = 177714360.

The previous prime is 390971557. The next prime is 390971657. The reversal of 390971636 is 636179093.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (44), and also a Moran number because the ratio is a prime number: 8885719 = 390971636 / (3 + 9 + 0 + 9 + 7 + 1 + 6 + 3 + 6).

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, 4442816 + ... + 4442903.

It is an arithmetic number, because the mean of its divisors is an integer number (62200040).

Almost surely, 2^390971636 is an apocalyptic number.

It is an amenable number.

390971636 is a deficient number, since it is larger than the sum of its proper divisors (355428844).

390971636 is a wasteful number, since it uses less digits than its factorization.

390971636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8885734 (or 8885732 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 44.

The square root of 390971636 is about 19773.0027057096. The cubic root of 390971636 is about 731.2205988520.

The spelling of 390971636 in words is "three hundred ninety million, nine hundred seventy-one thousand, six hundred thirty-six".