131891231 has 2 divisors, whose sum is σ = 131891232. Its totient is φ = 131891230.

The previous prime is 131891209. The next prime is 131891239. The reversal of 131891231 is 132198131.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 131891231 - 2⁶ = 131891167 is a prime.

It is a super-2 number, since 2×131891231² = 34790593629390722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 131891194 and 131891203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131891239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65945615 + 65945616.

It is an arithmetic number, because the mean of its divisors is an integer number (65945616).

Almost surely, 2^131891231 is an apocalyptic number.

131891231 is a deficient number, since it is larger than the sum of its proper divisors (1).

131891231 is an equidigital number, since it uses as much as digits as its factorization.

131891231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 29.

The square root of 131891231 is about 11484.3907544110. The cubic root of 131891231 is about 509.0244467784.

The spelling of 131891231 in words is "one hundred thirty-one million, eight hundred ninety-one thousand, two hundred thirty-one".