1231342531 has 2 divisors, whose sum is σ = 1231342532. Its totient is φ = 1231342530.

The previous prime is 1231342529. The next prime is 1231342577. The reversal of 1231342531 is 1352431321.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1231342531 - 2¹ = 1231342529 is a prime.

It is a super-2 number, since 2×1231342531² = 3032408857298971922, which contains 22 as substring.

Together with 1231342529, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1231342496 and 1231342505.

It is not a weakly prime, because it can be changed into another prime (1231342631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615671265 + 615671266.

It is an arithmetic number, because the mean of its divisors is an integer number (615671266).

Almost surely, 2^1231342531 is an apocalyptic number.

1231342531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231342531 is an equidigital number, since it uses as much as digits as its factorization.

1231342531 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 25.

The square root of 1231342531 is about 35090.4906064307. The cubic root of 1231342531 is about 1071.8309499315.

Adding to 1231342531 its reverse (1352431321), we get a palindrome (2583773852).

The spelling of 1231342531 in words is "one billion, two hundred thirty-one million, three hundred forty-two thousand, five hundred thirty-one".