1213111221231 has 32 divisors (see below), whose sum is σ = 2044550599168. Its totient is φ = 622588705920.

The previous prime is 1213111221221. The next prime is 1213111221253. The reversal of 1213111221231 is 1321221113121.

It is not a de Polignac number, because 1213111221231 - 2⁵ = 1213111221199 is a prime.

It is a super-2 number, since 2×1213111221231² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 1213111221198 and 1213111221207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213111221211) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 60038965 + ... + 60059166.

It is an arithmetic number, because the mean of its divisors is an integer number (63892206224).

Almost surely, 2^{1213111221231} is an apocalyptic number.

1213111221231 is a deficient number, since it is larger than the sum of its proper divisors (831439377937).

1213111221231 is a wasteful number, since it uses less digits than its factorization.

1213111221231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120098191.

The product of its digits is 144, while the sum is 21.

Adding to 1213111221231 its reverse (1321221113121), we get a palindrome (2534332334352).

The spelling of 1213111221231 in words is "one trillion, two hundred thirteen billion, one hundred eleven million, two hundred twenty-one thousand, two hundred thirty-one".