21660355451413 has 12 divisors (see below), whose sum is σ = 25235926272480. Its totient is φ = 18537144873912.

The previous prime is 21660355451387. The next prime is 21660355451509. The reversal of 21660355451413 is 31415455306612.

It is a de Polignac number, because none of the positive numbers 2^k-21660355451413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21660355451513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 343707273 + ... + 343770286.

It is an arithmetic number, because the mean of its divisors is an integer number (2102993856040).

Almost surely, 2^{21660355451413} is an apocalyptic number.

It is an amenable number.

21660355451413 is a deficient number, since it is larger than the sum of its proper divisors (3575570821067).

21660355451413 is an equidigital number, since it uses as much as digits as its factorization.

21660355451413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687478216 (or 687478209 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 46.

The spelling of 21660355451413 in words is "twenty-one trillion, six hundred sixty billion, three hundred fifty-five million, four hundred fifty-one thousand, four hundred thirteen".