391226863 has 4 divisors (see below), whose sum is σ = 401800600. Its totient is φ = 380653128.

The previous prime is 391226821. The next prime is 391226897. The reversal of 391226863 is 368622193.

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 391226863 - 2⁹ = 391226351 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 (391226063) 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, 5286813 + ... + 5286886.

It is an arithmetic number, because the mean of its divisors is an integer number (100450150).

Almost surely, 2^391226863 is an apocalyptic number.

391226863 is a deficient number, since it is larger than the sum of its proper divisors (10573737).

391226863 is a wasteful number, since it uses less digits than its factorization.

391226863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10573736.

The product of its digits is 93312, while the sum is 40.

The square root of 391226863 is about 19779.4555789587. The cubic root of 391226863 is about 731.3796782899.

The spelling of 391226863 in words is "three hundred ninety-one million, two hundred twenty-six thousand, eight hundred sixty-three".