231520143 has 8 divisors (see below), whose sum is σ = 308906800. Its totient is φ = 154240128.

The previous prime is 231520129. The next prime is 231520171. The reversal of 231520143 is 341025132.

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

It is not a de Polignac number, because 231520143 - 2⁸ = 231519887 is a prime.

It is a super-2 number, since 2×231520143² = 107203153229480898, 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 (231520043) 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, 21448 + ... + 30381.

It is an arithmetic number, because the mean of its divisors is an integer number (38613350).

Almost surely, 2^231520143 is an apocalyptic number.

231520143 is a deficient number, since it is larger than the sum of its proper divisors (77386657).

231520143 is a wasteful number, since it uses less digits than its factorization.

231520143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53321.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 231520143 is about 15215.7859803561. The cubic root of 231520143 is about 614.0394311310.

Adding to 231520143 its reverse (341025132), we get a palindrome (572545275).

The spelling of 231520143 in words is "two hundred thirty-one million, five hundred twenty thousand, one hundred forty-three".