390447391 has 4 divisors (see below), whose sum is σ = 396275032. Its totient is φ = 384619752.

The previous prime is 390447383. The next prime is 390447419. The reversal of 390447391 is 193744093.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 193744093 = 4391 ⋅44123.

It is a cyclic number.

It is not a de Polignac number, because 390447391 - 2³ = 390447383 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 (390447331) 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, 2913720 + ... + 2913853.

It is an arithmetic number, because the mean of its divisors is an integer number (99068758).

Almost surely, 2^390447391 is an apocalyptic number.

390447391 is a deficient number, since it is larger than the sum of its proper divisors (5827641).

390447391 is an equidigital number, since it uses as much as digits as its factorization.

390447391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5827640.

The product of its (nonzero) digits is 81648, while the sum is 40.

The square root of 390447391 is about 19759.7416734126. The cubic root of 390447391 is about 730.8936269594.

The spelling of 390447391 in words is "three hundred ninety million, four hundred forty-seven thousand, three hundred ninety-one".