2566421636767 has 2 divisors, whose sum is σ = 2566421636768. Its totient is φ = 2566421636766.

The previous prime is 2566421636759. The next prime is 2566421636797. The reversal of 2566421636767 is 7676361246652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2566421636767 - 2³ = 2566421636759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2566421636747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1283210818383 + 1283210818384.

It is an arithmetic number, because the mean of its divisors is an integer number (1283210818384).

Almost surely, 2^{2566421636767} is an apocalyptic number.

2566421636767 is a deficient number, since it is larger than the sum of its proper divisors (1).

2566421636767 is an equidigital number, since it uses as much as digits as its factorization.

2566421636767 is an evil number, because the sum of its binary digits is even.

The product of its digits is 91445760, while the sum is 61.

The spelling of 2566421636767 in words is "two trillion, five hundred sixty-six billion, four hundred twenty-one million, six hundred thirty-six thousand, seven hundred sixty-seven".