390617661 has 32 divisors (see below), whose sum is σ = 611968000. Its totient is φ = 221523120.

The previous prime is 390617657. The next prime is 390617663. The reversal of 390617661 is 166716093.

It is not a de Polignac number, because 390617661 - 2² = 390617657 is a prime.

It is a super-2 number, since 2×390617661² = 305164314170221842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390617663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141666 + ... + 144396.

It is an arithmetic number, because the mean of its divisors is an integer number (19124000).

Almost surely, 2^390617661 is an apocalyptic number.

It is an amenable number.

390617661 is a deficient number, since it is larger than the sum of its proper divisors (221350339).

390617661 is a wasteful number, since it uses less digits than its factorization.

390617661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2894 (or 2880 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 39.

The square root of 390617661 is about 19764.0497115343. The cubic root of 390617661 is about 730.9998565264. Note that the first 3 decimals are identical.

The spelling of 390617661 in words is "three hundred ninety million, six hundred seventeen thousand, six hundred sixty-one".