21663614336005 has 4 divisors (see below), whose sum is σ = 25996337203212. Its totient is φ = 17330891468800.

The previous prime is 21663614335999. The next prime is 21663614336051. The reversal of 21663614336005 is 50063341636612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2181215887236 + 19482398448769 = 1476894^2 + 4413887^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21663614336005 is a prime.

It is a super-2 number, since 2×21663614336005² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2166361433596 + ... + 2166361433605.

It is an arithmetic number, because the mean of its divisors is an integer number (6499084300803).

Almost surely, 2^{21663614336005} is an apocalyptic number.

It is an amenable number.

21663614336005 is a deficient number, since it is larger than the sum of its proper divisors (4332722867207).

21663614336005 is an equidigital number, since it uses as much as digits as its factorization.

21663614336005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4332722867206.

The product of its (nonzero) digits is 1399680, while the sum is 46.

The spelling of 21663614336005 in words is "twenty-one trillion, six hundred sixty-three billion, six hundred fourteen million, three hundred thirty-six thousand, five".