400142231 has 4 divisors (see below), whose sum is σ = 400218600. Its totient is φ = 400065864.

The previous prime is 400142227. The next prime is 400142233. The reversal of 400142231 is 132241004.

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 400142231 - 2² = 400142227 is a prime.

It is a super-2 number, since 2×400142231² = 320227610059314722, 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 (400142233) 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, 29696 + ... + 41013.

It is an arithmetic number, because the mean of its divisors is an integer number (100054650).

Almost surely, 2^400142231 is an apocalyptic number.

400142231 is a deficient number, since it is larger than the sum of its proper divisors (76369).

400142231 is an equidigital number, since it uses as much as digits as its factorization.

400142231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76368.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 400142231 is about 20003.5554589678. Note that the first 3 decimals coincide. The cubic root of 400142231 is about 736.8936199599.

Adding to 400142231 its reverse (132241004), we get a palindrome (532383235).

The spelling of 400142231 in words is "four hundred million, one hundred forty-two thousand, two hundred thirty-one".