131111311221 has 24 divisors (see below), whose sum is σ = 206653946304. Its totient is φ = 79440514560.

The previous prime is 131111311189. The next prime is 131111311231. The reversal of 131111311221 is 122113111131.

131111311221 is a `hidden beast` number, since 1 + 311 + 1 + 131 + 1 + 221 = 666.

It is not a de Polignac number, because 131111311221 - 2⁵ = 131111311189 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131111311194 and 131111311203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131111311231) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 208725 + ... + 552981.

It is an arithmetic number, because the mean of its divisors is an integer number (8610581096).

Almost surely, 2^131111311221 is an apocalyptic number.

131111311221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

131111311221 is a deficient number, since it is larger than the sum of its proper divisors (75542635083).

131111311221 is a wasteful number, since it uses less digits than its factorization.

131111311221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348121 (or 348118 counting only the distinct ones).

The product of its digits is 36, while the sum is 18.

Adding to 131111311221 its reverse (122113111131), we get a palindrome (253224422352).

The spelling of 131111311221 in words is "one hundred thirty-one billion, one hundred eleven million, three hundred eleven thousand, two hundred twenty-one".