390887121 has 4 divisors (see below), whose sum is σ = 521182832. Its totient is φ = 260591412.

The previous prime is 390887117. The next prime is 390887177. The reversal of 390887121 is 121788093.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 390887121 - 2² = 390887117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 390887121.

It is not an unprimeable number, because it can be changed into a prime (390887191) 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, 65147851 + ... + 65147856.

It is an arithmetic number, because the mean of its divisors is an integer number (130295708).

Almost surely, 2^390887121 is an apocalyptic number.

It is an amenable number.

390887121 is a deficient number, since it is larger than the sum of its proper divisors (130295711).

390887121 is a wasteful number, since it uses less digits than its factorization.

390887121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130295710.

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 390887121 is about 19770.8654590536. The cubic root of 390887121 is about 731.1679065706.

The spelling of 390887121 in words is "three hundred ninety million, eight hundred eighty-seven thousand, one hundred twenty-one".