2566216643 has 2 divisors, whose sum is σ = 2566216644. Its totient is φ = 2566216642.

The previous prime is 2566216621. The next prime is 2566216661. The reversal of 2566216643 is 3466126652.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2566216643 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2566216643.

It is not a weakly prime, because it can be changed into another prime (2566216603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1283108321 + 1283108322.

It is an arithmetic number, because the mean of its divisors is an integer number (1283108322).

Almost surely, 2^2566216643 is an apocalyptic number.

2566216643 is a deficient number, since it is larger than the sum of its proper divisors (1).

2566216643 is an equidigital number, since it uses as much as digits as its factorization.

2566216643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 41.

The square root of 2566216643 is about 50657.8389096890. The cubic root of 2566216643 is about 1369.0871861738.

The spelling of 2566216643 in words is "two billion, five hundred sixty-six million, two hundred sixteen thousand, six hundred forty-three".