394687391 has 8 divisors (see below), whose sum is σ = 451337760. Its totient is φ = 338103648.

The previous prime is 394687373. The next prime is 394687393. The reversal of 394687391 is 193786493.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 394687391 - 2²² = 390493087 is a prime.

It is a super-2 number, since 2×394687391² = 311556273228773762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394687393) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3236 + ... + 28281.

It is an arithmetic number, because the mean of its divisors is an integer number (56417220).

Almost surely, 2^394687391 is an apocalyptic number.

394687391 is a deficient number, since it is larger than the sum of its proper divisors (56650369).

394687391 is a wasteful number, since it uses less digits than its factorization.

394687391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33313.

The product of its digits is 979776, while the sum is 50.

The square root of 394687391 is about 19866.7408248057. The cubic root of 394687391 is about 733.5297810938.

The spelling of 394687391 in words is "three hundred ninety-four million, six hundred eighty-seven thousand, three hundred ninety-one".