21663410256213 has 16 divisors (see below), whose sum is σ = 31510540814400. Its totient is φ = 13129287092480.

The previous prime is 21663410256203. The next prime is 21663410256221. The reversal of 21663410256213 is 31265201436612.

It is a cyclic number.

It is not a de Polignac number, because 21663410256213 - 2⁶ = 21663410256149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21663410256203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8076253 + ... + 10418861.

It is an arithmetic number, because the mean of its divisors is an integer number (1969408800900).

Almost surely, 2^{21663410256213} is an apocalyptic number.

It is an amenable number.

21663410256213 is a deficient number, since it is larger than the sum of its proper divisors (9847130558187).

21663410256213 is a wasteful number, since it uses less digits than its factorization.

21663410256213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2622852.

The product of its (nonzero) digits is 311040, while the sum is 42.

The spelling of 21663410256213 in words is "twenty-one trillion, six hundred sixty-three billion, four hundred ten million, two hundred fifty-six thousand, two hundred thirteen".