216411178961 has 2 divisors, whose sum is σ = 216411178962. Its totient is φ = 216411178960.

The previous prime is 216411178913. The next prime is 216411179057. The reversal of 216411178961 is 169871114612.

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., 212492418961 + 3918760000 = 460969^2 + 62600^2 .

It is a cyclic number.

It is not a de Polignac number, because 216411178961 - 2²² = 216406984657 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (216411178561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108205589480 + 108205589481.

It is an arithmetic number, because the mean of its divisors is an integer number (108205589481).

Almost surely, 2^216411178961 is an apocalyptic number.

It is an amenable number.

216411178961 is a deficient number, since it is larger than the sum of its proper divisors (1).

216411178961 is an equidigital number, since it uses as much as digits as its factorization.

216411178961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 145152, while the sum is 47.

The spelling of 216411178961 in words is "two hundred sixteen billion, four hundred eleven million, one hundred seventy-eight thousand, nine hundred sixty-one".