21666230456535 has 48 divisors (see below), whose sum is σ = 45178706127360. Its totient is φ = 9383269728960.

The previous prime is 21666230456513. The next prime is 21666230456659. The reversal of 21666230456535 is 53565403266612.

It is a happy number.

It is not a de Polignac number, because 21666230456535 - 2²³ = 21666222067927 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1810038331 + ... + 1810050300.

It is an arithmetic number, because the mean of its divisors is an integer number (941223044320).

Almost surely, 2^{21666230456535} is an apocalyptic number.

21666230456535 is an abundant number, since it is smaller than the sum of its proper divisors (23512475670825).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21666230456535 is a wasteful number, since it uses less digits than its factorization.

21666230456535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3620088668 (or 3620088665 counting only the distinct ones).

The product of its (nonzero) digits is 23328000, while the sum is 54.

The spelling of 21666230456535 in words is "twenty-one trillion, six hundred sixty-six billion, two hundred thirty million, four hundred fifty-six thousand, five hundred thirty-five".