2564368021 has 2 divisors, whose sum is σ = 2564368022. Its totient is φ = 2564368020.

The previous prime is 2564367977. The next prime is 2564368063. The reversal of 2564368021 is 1208634652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2462640625 + 101727396 = 49625^2 + 10086^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2564368021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2564368091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1282184010 + 1282184011.

It is an arithmetic number, because the mean of its divisors is an integer number (1282184011).

Almost surely, 2^2564368021 is an apocalyptic number.

It is an amenable number.

2564368021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2564368021 is an equidigital number, since it uses as much as digits as its factorization.

2564368021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 2564368021 is about 50639.5894631858. The cubic root of 2564368021 is about 1368.7583580427.

The spelling of 2564368021 in words is "two billion, five hundred sixty-four million, three hundred sixty-eight thousand, twenty-one".