2163991002066 has 12 divisors (see below), whose sum is σ = 4688647171182. Its totient is φ = 721330334016.

The previous prime is 2163991002011. The next prime is 2163991002079. The reversal of 2163991002066 is 6602001993612.

2163991002066 is a `hidden beast` number, since 2 + 1 + 639 + 9 + 1 + 0 + 0 + 2 + 0 + 6 + 6 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1506154835025 + 657836167041 = 1227255^2 + 811071^2 .

It is a super-2 number, since 2×2163991002066² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 60110861151 + ... + 60110861186.

Almost surely, 2^{2163991002066} is an apocalyptic number.

2163991002066 is an abundant number, since it is smaller than the sum of its proper divisors (2524656169116).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2163991002066 is a wasteful number, since it uses less digits than its factorization.

2163991002066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120221722345 (or 120221722342 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

Adding to 2163991002066 its reverse (6602001993612), we get a palindrome (8765992995678).

The spelling of 2163991002066 in words is "two trillion, one hundred sixty-three billion, nine hundred ninety-one million, two thousand, sixty-six".