1231221013131 has 32 divisors (see below), whose sum is σ = 1754751651840. Its totient is φ = 766031533344.

The previous prime is 1231221013129. The next prime is 1231221013147. The reversal of 1231221013131 is 1313101221321.

It is not a de Polignac number, because 1231221013131 - 2¹ = 1231221013129 is a prime.

It is a super-2 number, since 2×1231221013131² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1231221013098 and 1231221013107.

It is not an unprimeable number, because it can be changed into a prime (1231221013151) 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, 2500900 + ... + 2952446.

It is an arithmetic number, because the mean of its divisors is an integer number (54835989120).

Almost surely, 2^{1231221013131} is an apocalyptic number.

1231221013131 is a deficient number, since it is larger than the sum of its proper divisors (523530638709).

1231221013131 is a wasteful number, since it uses less digits than its factorization.

1231221013131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452535.

The product of its (nonzero) digits is 216, while the sum is 21.

Adding to 1231221013131 its reverse (1313101221321), we get a palindrome (2544322234452).

The spelling of 1231221013131 in words is "one trillion, two hundred thirty-one billion, two hundred twenty-one million, thirteen thousand, one hundred thirty-one".