390631 has 4 divisors (see below), whose sum is σ = 403264. Its totient is φ = 378000.

The previous prime is 390581. The next prime is 390647. The reversal of 390631 is 136093.

390631 = T₁₄₃ + T₁₄₄ + ... + T₁₇₃.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 390631 - 2⁷ = 390503 is a prime.

It is a super-2 number, since 2×390631² = 305185156322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6270 + ... + 6331.

It is an arithmetic number, because the mean of its divisors is an integer number (100816).

2³⁹⁰⁶³¹ is an apocalyptic number.

390631 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

390631 is a deficient number, since it is larger than the sum of its proper divisors (12633).

390631 is a wasteful number, since it uses less digits than its factorization.

390631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12632.

The product of its (nonzero) digits is 486, while the sum is 22.

The square root of 390631 is about 625.0047999816. The cubic root of 390631 is about 73.1008177277.

The spelling of 390631 in words is "three hundred ninety thousand, six hundred thirty-one".