231405091 has 2 divisors, whose sum is σ = 231405092. Its totient is φ = 231405090.

The previous prime is 231405029. The next prime is 231405101. The reversal of 231405091 is 190504132.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 231405091 - 2¹³ = 231396899 is a prime.

It is a super-2 number, since 2×231405091² = 107096632281436562, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (231405491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115702545 + 115702546.

It is an arithmetic number, because the mean of its divisors is an integer number (115702546).

Almost surely, 2^231405091 is an apocalyptic number.

231405091 is a deficient number, since it is larger than the sum of its proper divisors (1).

231405091 is an equidigital number, since it uses as much as digits as its factorization.

231405091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 231405091 is about 15212.0048317110. The cubic root of 231405091 is about 613.9377003567.

The spelling of 231405091 in words is "two hundred thirty-one million, four hundred five thousand, ninety-one".