131231222221 has 8 divisors (see below), whose sum is σ = 144206308224. Its totient is φ = 118430298720.

The previous prime is 131231222219. The next prime is 131231222231. The reversal of 131231222221 is 122222132131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 131231222221 - 2¹ = 131231222219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131231222192 and 131231222201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131231222201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43539045 + ... + 43542058.

It is an arithmetic number, because the mean of its divisors is an integer number (18025788528).

Almost surely, 2^131231222221 is an apocalyptic number.

131231222221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

131231222221 is a deficient number, since it is larger than the sum of its proper divisors (12975086003).

131231222221 is a wasteful number, since it uses less digits than its factorization.

131231222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87081251.

The product of its digits is 576, while the sum is 22.

Adding to 131231222221 its reverse (122222132131), we get a palindrome (253453354352).

The spelling of 131231222221 in words is "one hundred thirty-one billion, two hundred thirty-one million, two hundred twenty-two thousand, two hundred twenty-one".