131003121221 has 4 divisors (see below), whose sum is σ = 149717852832. Its totient is φ = 112288389612.

The previous prime is 131003121191. The next prime is 131003121253. The reversal of 131003121221 is 122121300131.

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 a de Polignac number, because none of the positive numbers 2^k-131003121221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 131003121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131003121281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9357365795 + ... + 9357365808.

It is an arithmetic number, because the mean of its divisors is an integer number (37429463208).

Almost surely, 2^131003121221 is an apocalyptic number.

It is an amenable number.

131003121221 is a deficient number, since it is larger than the sum of its proper divisors (18714731611).

131003121221 is an equidigital number, since it uses as much as digits as its factorization.

131003121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18714731610.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 131003121221 its reverse (122121300131), we get a palindrome (253124421352).

The spelling of 131003121221 in words is "one hundred thirty-one billion, three million, one hundred twenty-one thousand, two hundred twenty-one".