216511236274961 has 2 divisors, whose sum is σ = 216511236274962. Its totient is φ = 216511236274960.

The previous prime is 216511236274937. The next prime is 216511236275021. The reversal of 216511236274961 is 169472632115612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216391160857600 + 120075417361 = 14710240^2 + 346519^2 .

It is a cyclic number.

It is not a de Polignac number, because 216511236274961 - 2³⁴ = 216494056405777 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 216511236274897 and 216511236274906.

It is not a weakly prime, because it can be changed into another prime (216511230274961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108255618137480 + 108255618137481.

It is an arithmetic number, because the mean of its divisors is an integer number (108255618137481).

Almost surely, 2^{216511236274961} is an apocalyptic number.

It is an amenable number.

216511236274961 is a deficient number, since it is larger than the sum of its proper divisors (1).

216511236274961 is an equidigital number, since it uses as much as digits as its factorization.

216511236274961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6531840, while the sum is 56.

The spelling of 216511236274961 in words is "two hundred sixteen trillion, five hundred eleven billion, two hundred thirty-six million, two hundred seventy-four thousand, nine hundred sixty-one".