2668634121557 has 2 divisors, whose sum is σ = 2668634121558. Its totient is φ = 2668634121556.

The previous prime is 2668634121463. The next prime is 2668634121611. The reversal of 2668634121557 is 7551214368662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2102386901521 + 566247220036 = 1449961^2 + 752494^2 .

It is a cyclic number.

It is not a de Polignac number, because 2668634121557 - 2¹⁴ = 2668634105173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2668634121457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1334317060778 + 1334317060779.

It is an arithmetic number, because the mean of its divisors is an integer number (1334317060779).

Almost surely, 2^{2668634121557} is an apocalyptic number.

It is an amenable number.

2668634121557 is a deficient number, since it is larger than the sum of its proper divisors (1).

2668634121557 is an equidigital number, since it uses as much as digits as its factorization.

2668634121557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14515200, while the sum is 56.

The spelling of 2668634121557 in words is "two trillion, six hundred sixty-eight billion, six hundred thirty-four million, one hundred twenty-one thousand, five hundred fifty-seven".