21669315938563 has 2 divisors, whose sum is σ = 21669315938564. Its totient is φ = 21669315938562.

The previous prime is 21669315938467. The next prime is 21669315938587. The reversal of 21669315938563 is 36583951396612.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21669315938563 is a prime.

It is not a weakly prime, because it can be changed into another prime (21669315933563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10834657969281 + 10834657969282.

It is an arithmetic number, because the mean of its divisors is an integer number (10834657969282).

Almost surely, 2^{21669315938563} is an apocalyptic number.

21669315938563 is a deficient number, since it is larger than the sum of its proper divisors (1).

21669315938563 is an equidigital number, since it uses as much as digits as its factorization.

21669315938563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 188956800, while the sum is 67.

The spelling of 21669315938563 in words is "twenty-one trillion, six hundred sixty-nine billion, three hundred fifteen million, nine hundred thirty-eight thousand, five hundred sixty-three".