1231442531 has 32 divisors (see below), whose sum is σ = 1398974976. Its totient is φ = 1083482400.

The previous prime is 1231442519. The next prime is 1231442551. The reversal of 1231442531 is 1352441321.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-1231442531 is a prime.

It is a super-2 number, since 2×1231442531² = 3032901414311371922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231442531.

It is not an unprimeable number, because it can be changed into a prime (1231442551) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7843505 + ... + 7843661.

It is an arithmetic number, because the mean of its divisors is an integer number (43717968).

Almost surely, 2^1231442531 is an apocalyptic number.

1231442531 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1231442531 is a deficient number, since it is larger than the sum of its proper divisors (167532445).

1231442531 is an equidigital number, since it uses as much as digits as its factorization.

1231442531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344 (or 322 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 1231442531 is about 35091.9154649614. The cubic root of 1231442531 is about 1071.8599643855.

Adding to 1231442531 its reverse (1352441321), we get a palindrome (2583883852).

It can be divided in two parts, 12314 and 42531, that added together give a palindrome (54845).

The spelling of 1231442531 in words is "one billion, two hundred thirty-one million, four hundred forty-two thousand, five hundred thirty-one".