131221440277 has 2 divisors, whose sum is σ = 131221440278. Its totient is φ = 131221440276.

The previous prime is 131221440271. The next prime is 131221440323. The reversal of 131221440277 is 772044122131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80752020561 + 50469419716 = 284169^2 + 224654^2 .

It is a cyclic number.

It is not a de Polignac number, because 131221440277 - 2¹⁹ = 131220915989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131221440271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65610720138 + 65610720139.

It is an arithmetic number, because the mean of its divisors is an integer number (65610720139).

Almost surely, 2^131221440277 is an apocalyptic number.

It is an amenable number.

131221440277 is a deficient number, since it is larger than the sum of its proper divisors (1).

131221440277 is an equidigital number, since it uses as much as digits as its factorization.

131221440277 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18816, while the sum is 34.

The spelling of 131221440277 in words is "one hundred thirty-one billion, two hundred twenty-one million, four hundred forty thousand, two hundred seventy-seven".