2660734400021 has 2 divisors, whose sum is σ = 2660734400022. Its totient is φ = 2660734400020.

The previous prime is 2660734399987. The next prime is 2660734400033. The reversal of 2660734400021 is 1200044370662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2659789144996 + 945255025 = 1630886^2 + 30745^2 .

It is a cyclic number.

It is not a de Polignac number, because 2660734400021 - 2²⁶ = 2660667291157 is a prime.

It is a super-2 number, since 2×2660734400021² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2660734400081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330367200010 + 1330367200011.

It is an arithmetic number, because the mean of its divisors is an integer number (1330367200011).

Almost surely, 2^{2660734400021} is an apocalyptic number.

It is an amenable number.

2660734400021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2660734400021 is an equidigital number, since it uses as much as digits as its factorization.

2660734400021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 35.

Adding to 2660734400021 its reverse (1200044370662), we get a palindrome (3860778770683).

The spelling of 2660734400021 in words is "two trillion, six hundred sixty billion, seven hundred thirty-four million, four hundred thousand, twenty-one".