131221193 has 2 divisors, whose sum is σ = 131221194. Its totient is φ = 131221192.

The previous prime is 131221183. The next prime is 131221213. The reversal of 131221193 is 391122131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86638864 + 44582329 = 9308^2 + 6677^2 .

It is a cyclic number.

It is not a de Polignac number, because 131221193 - 2⁴ = 131221177 is a prime.

It is a nialpdrome in base 8.

It is not a weakly prime, because it can be changed into another prime (131221183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65610596 + 65610597.

It is an arithmetic number, because the mean of its divisors is an integer number (65610597).

Almost surely, 2^131221193 is an apocalyptic number.

It is an amenable number.

131221193 is a deficient number, since it is larger than the sum of its proper divisors (1).

131221193 is an equidigital number, since it uses as much as digits as its factorization.

131221193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 324, while the sum is 23.

The square root of 131221193 is about 11455.1819278438. The cubic root of 131221193 is about 508.1609955856.

The spelling of 131221193 in words is "one hundred thirty-one million, two hundred twenty-one thousand, one hundred ninety-three".