1221330031131 has 32 divisors (see below), whose sum is σ = 1866362876928. Its totient is φ = 695920279680.

The previous prime is 1221330031093. The next prime is 1221330031147. The reversal of 1221330031131 is 1311300331221.

It is a happy number.

It is not a de Polignac number, because 1221330031131 - 2²² = 1221325836827 is a prime.

It is a super-2 number, since 2×1221330031131² (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 = 1221330031098 and 1221330031107.

It is not an unprimeable number, because it can be changed into a prime (1221330031631) 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, 94545685 + ... + 94558601.

It is an arithmetic number, because the mean of its divisors is an integer number (58323839904).

Almost surely, 2^{1221330031131} is an apocalyptic number.

1221330031131 is a deficient number, since it is larger than the sum of its proper divisors (645032845797).

1221330031131 is a wasteful number, since it uses less digits than its factorization.

1221330031131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25371.

The product of its (nonzero) digits is 324, while the sum is 21.

Adding to 1221330031131 its reverse (1311300331221), we get a palindrome (2532630362352).

The spelling of 1221330031131 in words is "one trillion, two hundred twenty-one billion, three hundred thirty million, thirty-one thousand, one hundred thirty-one".