201331012261 has 2 divisors, whose sum is σ = 201331012262. Its totient is φ = 201331012260.

The previous prime is 201331012249. The next prime is 201331012403. The reversal of 201331012261 is 162210133102.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110869020900 + 90461991361 = 332970^2 + 300769^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201331012261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201331052261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100665506130 + 100665506131.

It is an arithmetic number, because the mean of its divisors is an integer number (100665506131).

Almost surely, 2^201331012261 is an apocalyptic number.

It is an amenable number.

201331012261 is a deficient number, since it is larger than the sum of its proper divisors (1).

201331012261 is an equidigital number, since it uses as much as digits as its factorization.

201331012261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 22.

Adding to 201331012261 its reverse (162210133102), we get a palindrome (363541145363).

The spelling of 201331012261 in words is "two hundred one billion, three hundred thirty-one million, twelve thousand, two hundred sixty-one".