131537646221 has 2 divisors, whose sum is σ = 131537646222. Its totient is φ = 131537646220.

The previous prime is 131537646211. The next prime is 131537646257. The reversal of 131537646221 is 122646735131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 94012144996 + 37525501225 = 306614^2 + 193715^2 .

It is an emirp because it is prime and its reverse (122646735131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 131537646221 - 2¹⁴ = 131537629837 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (131537646211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65768823110 + 65768823111.

It is an arithmetic number, because the mean of its divisors is an integer number (65768823111).

Almost surely, 2^131537646221 is an apocalyptic number.

It is an amenable number.

131537646221 is a deficient number, since it is larger than the sum of its proper divisors (1).

131537646221 is an equidigital number, since it uses as much as digits as its factorization.

131537646221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 181440, while the sum is 41.

The spelling of 131537646221 in words is "one hundred thirty-one billion, five hundred thirty-seven million, six hundred forty-six thousand, two hundred twenty-one".