2166616056251 has 2 divisors, whose sum is σ = 2166616056252. Its totient is φ = 2166616056250.

The previous prime is 2166616056217. The next prime is 2166616056299. The reversal of 2166616056251 is 1526506166612.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2166616056251 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2166616056196 and 2166616056205.

It is not a weakly prime, because it can be changed into another prime (2166616056211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1083308028125 + 1083308028126.

It is an arithmetic number, because the mean of its divisors is an integer number (1083308028126).

Almost surely, 2^{2166616056251} is an apocalyptic number.

2166616056251 is a deficient number, since it is larger than the sum of its proper divisors (1).

2166616056251 is an equidigital number, since it uses as much as digits as its factorization.

2166616056251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 777600, while the sum is 47.

The spelling of 2166616056251 in words is "two trillion, one hundred sixty-six billion, six hundred sixteen million, fifty-six thousand, two hundred fifty-one".