131023211221 has 4 divisors (see below), whose sum is σ = 149740812832. Its totient is φ = 112305609612.

The previous prime is 131023211197. The next prime is 131023211237. The reversal of 131023211221 is 122112320131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 131023211221 - 2²⁵ = 130989656789 is a prime.

It is a super-4 number, since 4×131023211221⁴ (a number of 46 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131023211521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9358800795 + ... + 9358800808.

It is an arithmetic number, because the mean of its divisors is an integer number (37435203208).

Almost surely, 2^131023211221 is an apocalyptic number.

It is an amenable number.

131023211221 is a deficient number, since it is larger than the sum of its proper divisors (18717601611).

131023211221 is an equidigital number, since it uses as much as digits as its factorization.

131023211221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18717601610.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 131023211221 its reverse (122112320131), we get a palindrome (253135531352).

The spelling of 131023211221 in words is "one hundred thirty-one billion, twenty-three million, two hundred eleven thousand, two hundred twenty-one".