390257187 has 4 divisors (see below), whose sum is σ = 520342920. Its totient is φ = 260171456.

The previous prime is 390257183. The next prime is 390257191. The reversal of 390257187 is 781752093.

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

It is an interprime number because it is at equal distance from previous prime (390257183) and next prime (390257191).

It is a cyclic number.

It is not a de Polignac number, because 390257187 - 2² = 390257183 is a prime.

It is not an unprimeable number, because it can be changed into a prime (390257183) 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, 65042862 + ... + 65042867.

It is an arithmetic number, because the mean of its divisors is an integer number (130085730).

Almost surely, 2^390257187 is an apocalyptic number.

390257187 is a deficient number, since it is larger than the sum of its proper divisors (130085733).

390257187 is a wasteful number, since it uses less digits than its factorization.

390257187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130085732.

The product of its (nonzero) digits is 105840, while the sum is 42.

The square root of 390257187 is about 19754.9281699529. The cubic root of 390257187 is about 730.7749242653.

The spelling of 390257187 in words is "three hundred ninety million, two hundred fifty-seven thousand, one hundred eighty-seven".