1231312121 has 8 divisors (see below), whose sum is σ = 1326480960. Its totient is φ = 1136207952.

The previous prime is 1231312111. The next prime is 1231312151. The reversal of 1231312121 is 1212131321.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231312121 is a prime.

It is a super-2 number, since 2×1231312121² = 3032259078643037282, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231312121.

It is not an unprimeable number, because it can be changed into a prime (1231312111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27836 + ... + 56898.

It is an arithmetic number, because the mean of its divisors is an integer number (165810120).

Almost surely, 2^1231312121 is an apocalyptic number.

It is an amenable number.

1231312121 is a deficient number, since it is larger than the sum of its proper divisors (95168839).

1231312121 is a wasteful number, since it uses less digits than its factorization.

1231312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32335.

The product of its digits is 72, while the sum is 17.

The square root of 1231312121 is about 35090.0572954790. The cubic root of 1231312121 is about 1071.8221263246.

Adding to 1231312121 its reverse (1212131321), we get a palindrome (2443443442).

The spelling of 1231312121 in words is "one billion, two hundred thirty-one million, three hundred twelve thousand, one hundred twenty-one".