1231262531 has 2 divisors, whose sum is σ = 1231262532. Its totient is φ = 1231262530.

The previous prime is 1231262521. The next prime is 1231262537. The reversal of 1231262531 is 1352621321.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231262531 - 2²⁶ = 1164153667 is a prime.

It is a super-2 number, since 2×1231262531² = 3032014840489051922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1231262531.

It is not a weakly prime, because it can be changed into another prime (1231262537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615631265 + 615631266.

It is an arithmetic number, because the mean of its divisors is an integer number (615631266).

Almost surely, 2^1231262531 is an apocalyptic number.

1231262531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231262531 is an equidigital number, since it uses as much as digits as its factorization.

1231262531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 26.

The square root of 1231262531 is about 35089.3506779479. The cubic root of 1231262531 is about 1071.8077372373.

Adding to 1231262531 its reverse (1352621321), we get a palindrome (2583883852).

The spelling of 1231262531 in words is "one billion, two hundred thirty-one million, two hundred sixty-two thousand, five hundred thirty-one".