2565870421663 has 2 divisors, whose sum is σ = 2565870421664. Its totient is φ = 2565870421662.

The previous prime is 2565870421661. The next prime is 2565870421703. The reversal of 2565870421663 is 3661240785652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2565870421663 - 2¹ = 2565870421661 is a prime.

It is a super-2 number, since 2×2565870421663² (a number of 26 digits) contains 22 as substring.

Together with 2565870421661, 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 (2565870421661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1282935210831 + 1282935210832.

It is an arithmetic number, because the mean of its divisors is an integer number (1282935210832).

Almost surely, 2^{2565870421663} is an apocalyptic number.

2565870421663 is a deficient number, since it is larger than the sum of its proper divisors (1).

2565870421663 is an equidigital number, since it uses as much as digits as its factorization.

2565870421663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14515200, while the sum is 55.

The spelling of 2565870421663 in words is "two trillion, five hundred sixty-five billion, eight hundred seventy million, four hundred twenty-one thousand, six hundred sixty-three".