231540871 has 4 divisors (see below), whose sum is σ = 231612544. Its totient is φ = 231469200.

The previous prime is 231540787. The next prime is 231540877. The reversal of 231540871 is 178045132.

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 231540871 - 2¹⁷ = 231409799 is a prime.

It is a super-2 number, since 2×231540871² = 107222349886877282, 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 (231540877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30750 + ... + 37531.

It is an arithmetic number, because the mean of its divisors is an integer number (57903136).

Almost surely, 2^231540871 is an apocalyptic number.

231540871 is a deficient number, since it is larger than the sum of its proper divisors (71673).

231540871 is an equidigital number, since it uses as much as digits as its factorization.

231540871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71672.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 231540871 is about 15216.4670998231. The cubic root of 231540871 is about 614.0577555690.

The spelling of 231540871 in words is "two hundred thirty-one million, five hundred forty thousand, eight hundred seventy-one".