215112031261 has 2 divisors, whose sum is σ = 215112031262. Its totient is φ = 215112031260.

The previous prime is 215112031247. The next prime is 215112031307. The reversal of 215112031261 is 162130211512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 183338968761 + 31773062500 = 428181^2 + 178250^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215112031261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (215112031231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107556015630 + 107556015631.

It is an arithmetic number, because the mean of its divisors is an integer number (107556015631).

Almost surely, 2^215112031261 is an apocalyptic number.

It is an amenable number.

215112031261 is a deficient number, since it is larger than the sum of its proper divisors (1).

215112031261 is an equidigital number, since it uses as much as digits as its factorization.

215112031261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 25.

Adding to 215112031261 its reverse (162130211512), we get a palindrome (377242242773).

The spelling of 215112031261 in words is "two hundred fifteen billion, one hundred twelve million, thirty-one thousand, two hundred sixty-one".