1231213031 has 4 divisors (see below), whose sum is σ = 1232907312. Its totient is φ = 1229518752.

The previous prime is 1231213007. The next prime is 1231213033. The reversal of 1231213031 is 1303121321.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1231213031 - 2⁶ = 1231212967 is a prime.

It is a super-2 number, since 2×1231213031² = 3031771055408413922, 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 (1231213033) 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, 846050 + ... + 847503.

It is an arithmetic number, because the mean of its divisors is an integer number (308226828).

Almost surely, 2^1231213031 is an apocalyptic number.

1231213031 is a deficient number, since it is larger than the sum of its proper divisors (1694281).

1231213031 is an equidigital number, since it uses as much as digits as its factorization.

1231213031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1694280.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 1231213031 is about 35088.6453286530. The cubic root of 1231213031 is about 1071.7933738791.

Adding to 1231213031 its reverse (1303121321), we get a palindrome (2534334352).

The spelling of 1231213031 in words is "one billion, two hundred thirty-one million, two hundred thirteen thousand, thirty-one".