1213111312 has 40 divisors (see below), whose sum is σ = 2693039936. Its totient is φ = 518576256.

The previous prime is 1213111307. The next prime is 1213111327. The reversal of 1213111312 is 2131113121.

It is a happy number.

It is a super-2 number, since 2×1213111312² = 2943278110604722688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30823 + ... + 58105.

Almost surely, 2^1213111312 is an apocalyptic number.

It is an amenable number.

1213111312 is an abundant number, since it is smaller than the sum of its proper divisors (1479928624).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1213111312 is a wasteful number, since it uses less digits than its factorization.

1213111312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27695 (or 27689 counting only the distinct ones).

The product of its digits is 36, while the sum is 16.

The square root of 1213111312 is about 34829.7475155936. The cubic root of 1213111312 is about 1066.5147941760.

Adding to 1213111312 its reverse (2131113121), we get a palindrome (3344224433).

The spelling of 1213111312 in words is "one billion, two hundred thirteen million, one hundred eleven thousand, three hundred twelve".