1213121313 has 16 divisors (see below), whose sum is σ = 1806256000. Its totient is φ = 804679920.

The previous prime is 1213121311. The next prime is 1213121323. The reversal of 1213121313 is 3131213121.

It is not a de Polignac number, because 1213121313 - 2¹ = 1213121311 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1213121311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107518 + ... + 118263.

It is an arithmetic number, because the mean of its divisors is an integer number (112891000).

Almost surely, 2^1213121313 is an apocalyptic number.

It is an amenable number.

1213121313 is a deficient number, since it is larger than the sum of its proper divisors (593134687).

1213121313 is a wasteful number, since it uses less digits than its factorization.

1213121313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225989 (or 225983 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 1213121313 is about 34829.8910851010. The cubic root of 1213121313 is about 1066.5177249829.

Adding to 1213121313 its reverse (3131213121), we get a palindrome (4344334434).

The spelling of 1213121313 in words is "one billion, two hundred thirteen million, one hundred twenty-one thousand, three hundred thirteen".