231550031 has 2 divisors, whose sum is σ = 231550032. Its totient is φ = 231550030.

The previous prime is 231550021. The next prime is 231550051. The reversal of 231550031 is 130055132.

It is an a-pointer prime, because the next prime (231550051) can be obtained adding 231550031 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 231550031 - 2¹⁴ = 231533647 is a prime.

It is a super-2 number, since 2×231550031² = 107230833712201922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 231549985 and 231550012.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231550021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115775015 + 115775016.

It is an arithmetic number, because the mean of its divisors is an integer number (115775016).

Almost surely, 2^231550031 is an apocalyptic number.

231550031 is a deficient number, since it is larger than the sum of its proper divisors (1).

231550031 is an equidigital number, since it uses as much as digits as its factorization.

231550031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 450, while the sum is 20.

The square root of 231550031 is about 15216.7680865550. The cubic root of 231550031 is about 614.0658530521.

The spelling of 231550031 in words is "two hundred thirty-one million, five hundred fifty thousand, thirty-one".