1231231541 has 4 divisors (see below), whose sum is σ = 1232426784. Its totient is φ = 1230036300.

The previous prime is 1231231537. The next prime is 1231231543. The reversal of 1231231541 is 1451321321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1231231541 - 2² = 1231231537 is a prime.

It is a super-2 number, since 2×1231231541² = 3031862215106469362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231231543) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 596075 + ... + 598136.

It is an arithmetic number, because the mean of its divisors is an integer number (308106696).

Almost surely, 2^1231231541 is an apocalyptic number.

It is an amenable number.

1231231541 is a deficient number, since it is larger than the sum of its proper divisors (1195243).

1231231541 is a wasteful number, since it uses less digits than its factorization.

1231231541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195242.

The product of its digits is 720, while the sum is 23.

The square root of 1231231541 is about 35088.9090882005. The cubic root of 1231231541 is about 1071.7987449496.

Adding to 1231231541 its reverse (1451321321), we get a palindrome (2682552862).

The spelling of 1231231541 in words is "one billion, two hundred thirty-one million, two hundred thirty-one thousand, five hundred forty-one".