21660355635434 has 8 divisors (see below), whose sum is σ = 32510141504868. Its totient is φ = 10823641800480.

The previous prime is 21660355635409. The next prime is 21660355635439. The reversal of 21660355635434 is 43453655306612.

It can be written as a sum of positive squares in 2 ways, for example, as 21606553441225 + 53802194209 = 4648285^2 + 231953^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21660355635439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3268004477 + ... + 3268011104.

Almost surely, 2^{21660355635434} is an apocalyptic number.

21660355635434 is a deficient number, since it is larger than the sum of its proper divisors (10849785869434).

21660355635434 is a wasteful number, since it uses less digits than its factorization.

21660355635434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6536017240.

The product of its (nonzero) digits is 23328000, while the sum is 53.

The spelling of 21660355635434 in words is "twenty-one trillion, six hundred sixty billion, three hundred fifty-five million, six hundred thirty-five thousand, four hundred thirty-four".