131090221 has 2 divisors, whose sum is σ = 131090222. Its totient is φ = 131090220.

The previous prime is 131090189. The next prime is 131090249. The reversal of 131090221 is 122090131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68062500 + 63027721 = 8250^2 + 7939^2 .

It is an emirp because it is prime and its reverse (122090131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131090221 - 2⁵ = 131090189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131094221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65545110 + 65545111.

It is an arithmetic number, because the mean of its divisors is an integer number (65545111).

Almost surely, 2^131090221 is an apocalyptic number.

It is an amenable number.

131090221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131090221 is an equidigital number, since it uses as much as digits as its factorization.

131090221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 131090221 is about 11449.4637865710. The cubic root of 131090221 is about 507.9918739788.

The spelling of 131090221 in words is "one hundred thirty-one million, ninety thousand, two hundred twenty-one".