2166616161623 has 2 divisors, whose sum is σ = 2166616161624. Its totient is φ = 2166616161622.

The previous prime is 2166616161601. The next prime is 2166616161701. The reversal of 2166616161623 is 3261616166612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2166616161623 - 2¹² = 2166616157527 is a prime.

It is a super-3 number, since 3×2166616161623³ (a number of 38 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2166616163623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1083308080811 + 1083308080812.

It is an arithmetic number, because the mean of its divisors is an integer number (1083308080812).

Almost surely, 2^{2166616161623} is an apocalyptic number.

2166616161623 is a deficient number, since it is larger than the sum of its proper divisors (1).

2166616161623 is an equidigital number, since it uses as much as digits as its factorization.

2166616161623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 559872, while the sum is 47.

The spelling of 2166616161623 in words is "two trillion, one hundred sixty-six billion, six hundred sixteen million, one hundred sixty-one thousand, six hundred twenty-three".