231538 has 4 divisors (see below), whose sum is σ = 347310. Its totient is φ = 115768.

The previous prime is 231533. The next prime is 231547. The reversal of 231538 is 835132.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 124609 + 106929 = 353^2 + 327^2 .

It is not an unprimeable number, because it can be changed into a prime (231533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57883 + ... + 57886.

2²³¹⁵³⁸ is an apocalyptic number.

231538 is a deficient number, since it is larger than the sum of its proper divisors (115772).

231538 is a wasteful number, since it uses less digits than its factorization.

231538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115771.

The product of its digits is 720, while the sum is 22.

The square root of 231538 is about 481.1839565073. The cubic root of 231538 is about 61.4055217548.

The spelling of 231538 in words is "two hundred thirty-one thousand, five hundred thirty-eight".