2164644843281 has 2 divisors, whose sum is σ = 2164644843282. Its totient is φ = 2164644843280.

The previous prime is 2164644843203. The next prime is 2164644843287. The reversal of 2164644843281 is 1823484464612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1928234954881 + 236409888400 = 1388609^2 + 486220^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2164644843281 is a prime.

It is a super-2 number, since 2×2164644843281² (a number of 25 digits) contains 22 as substring.

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 (2164644843287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1082322421640 + 1082322421641.

It is an arithmetic number, because the mean of its divisors is an integer number (1082322421641).

Almost surely, 2^{2164644843281} is an apocalyptic number.

It is an amenable number.

2164644843281 is a deficient number, since it is larger than the sum of its proper divisors (1).

2164644843281 is an equidigital number, since it uses as much as digits as its factorization.

2164644843281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7077888, while the sum is 53.

The spelling of 2164644843281 in words is "two trillion, one hundred sixty-four billion, six hundred forty-four million, eight hundred forty-three thousand, two hundred eighty-one".