400393731 has 8 divisors (see below), whose sum is σ = 534633664. Its totient is φ = 266541480.

The previous prime is 400393717. The next prime is 400393739. The reversal of 400393731 is 137393004.

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

It is not a de Polignac number, because 400393731 - 2⁵ = 400393699 is a prime.

It is a super-2 number, since 2×400393731² = 320630279648200722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400393739) 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, 94501 + ... + 98646.

It is an arithmetic number, because the mean of its divisors is an integer number (66829208).

Almost surely, 2^400393731 is an apocalyptic number.

400393731 is a deficient number, since it is larger than the sum of its proper divisors (134239933).

400393731 is a wasteful number, since it uses less digits than its factorization.

400393731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193841.

The product of its (nonzero) digits is 6804, while the sum is 30.

The square root of 400393731 is about 20009.8408539398. The cubic root of 400393731 is about 737.0479733511.

The spelling of 400393731 in words is "four hundred million, three hundred ninety-three thousand, seven hundred thirty-one".