2168980861 has 2 divisors, whose sum is σ = 2168980862. Its totient is φ = 2168980860.

The previous prime is 2168980859. The next prime is 2168980871. The reversal of 2168980861 is 1680898612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2047562500 + 121418361 = 45250^2 + 11019^2 .

It is a cyclic number.

It is not a de Polignac number, because 2168980861 - 2¹ = 2168980859 is a prime.

Together with 2168980859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2168980841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1084490430 + 1084490431.

It is an arithmetic number, because the mean of its divisors is an integer number (1084490431).

Almost surely, 2^2168980861 is an apocalyptic number.

It is an amenable number.

2168980861 is a deficient number, since it is larger than the sum of its proper divisors (1).

2168980861 is an equidigital number, since it uses as much as digits as its factorization.

2168980861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 49.

The square root of 2168980861 is about 46572.3186130989. The cubic root of 2168980861 is about 1294.4498810782.

The spelling of 2168980861 in words is "two billion, one hundred sixty-eight million, nine hundred eighty thousand, eight hundred sixty-one".