21152542226161 has 2 divisors, whose sum is σ = 21152542226162. Its totient is φ = 21152542226160.

The previous prime is 21152542225933. The next prime is 21152542226227. The reversal of 21152542226161 is 16162224525112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10691722832400 + 10460819393761 = 3269820^2 + 3234319^2 .

It is a cyclic number.

It is not a de Polignac number, because 21152542226161 - 2³¹ = 21150394742513 is a prime.

It is not a weakly prime, because it can be changed into another prime (21152542226861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10576271113080 + 10576271113081.

It is an arithmetic number, because the mean of its divisors is an integer number (10576271113081).

Almost surely, 2^{21152542226161} is an apocalyptic number.

It is an amenable number.

21152542226161 is a deficient number, since it is larger than the sum of its proper divisors (1).

21152542226161 is an equidigital number, since it uses as much as digits as its factorization.

21152542226161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 115200, while the sum is 40.

The spelling of 21152542226161 in words is "twenty-one trillion, one hundred fifty-two billion, five hundred forty-two million, two hundred twenty-six thousand, one hundred sixty-one".