231142391 has 8 divisors (see below), whose sum is σ = 243714480. Its totient is φ = 218611008.

The previous prime is 231142369. The next prime is 231142393. The reversal of 231142391 is 193241132.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231142391 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 231142391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231142393) 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, 1865 + ... + 21581.

It is an arithmetic number, because the mean of its divisors is an integer number (30464310).

Almost surely, 2^231142391 is an apocalyptic number.

231142391 is a deficient number, since it is larger than the sum of its proper divisors (12572089).

231142391 is a wasteful number, since it uses less digits than its factorization.

231142391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20353.

The product of its digits is 1296, while the sum is 26.

The square root of 231142391 is about 15203.3677519160. The cubic root of 231142391 is about 613.7052904549.

The spelling of 231142391 in words is "two hundred thirty-one million, one hundred forty-two thousand, three hundred ninety-one".