21660563124145 has 16 divisors (see below), whose sum is σ = 28356901410240. Its totient is φ = 15752439518400.

The previous prime is 21660563124127. The next prime is 21660563124173. The reversal of 21660563124145 is 54142136506612.

It is not a de Polignac number, because 21660563124145 - 2²⁵ = 21660529569713 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21660563124095 and 21660563124104.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7460775 + ... + 9949084.

It is an arithmetic number, because the mean of its divisors is an integer number (1772306338140).

Almost surely, 2^{21660563124145} is an apocalyptic number.

It is an amenable number.

21660563124145 is a deficient number, since it is larger than the sum of its proper divisors (6696338286095).

21660563124145 is a wasteful number, since it uses less digits than its factorization.

21660563124145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17432496.

The product of its (nonzero) digits is 1036800, while the sum is 46.

The spelling of 21660563124145 in words is "twenty-one trillion, six hundred sixty billion, five hundred sixty-three million, one hundred twenty-four thousand, one hundred forty-five".