390908887 has 4 divisors (see below), whose sum is σ = 396743416. Its totient is φ = 385074360.

The previous prime is 390908857. The next prime is 390908899. The reversal of 390908887 is 788809093.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 788809093 = 10177 ⋅77509.

It is a cyclic number.

It is not a de Polignac number, because 390908887 - 2¹¹ = 390906839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390908857) 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, 2917164 + ... + 2917297.

It is an arithmetic number, because the mean of its divisors is an integer number (99185854).

Almost surely, 2^390908887 is an apocalyptic number.

390908887 is a deficient number, since it is larger than the sum of its proper divisors (5834529).

390908887 is an equidigital number, since it uses as much as digits as its factorization.

390908887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5834528.

The product of its (nonzero) digits is 870912, while the sum is 52.

The square root of 390908887 is about 19771.4159078201. The cubic root of 390908887 is about 731.1814776711.

The spelling of 390908887 in words is "three hundred ninety million, nine hundred eight thousand, eight hundred eighty-seven".