21356207021633 has 32 divisors (see below), whose sum is σ = 25234885435392. Its totient is φ = 17877535790400.

The previous prime is 21356207021599. The next prime is 21356207021641. The reversal of 21356207021633 is 33612070265312.

It is not a de Polignac number, because 21356207021633 - 2¹⁰ = 21356207020609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21356207021333) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13995941 + ... + 15446642.

It is an arithmetic number, because the mean of its divisors is an integer number (788590169856).

Almost surely, 2^{21356207021633} is an apocalyptic number.

21356207021633 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21356207021633 is a deficient number, since it is larger than the sum of its proper divisors (3878678413759).

21356207021633 is a wasteful number, since it uses less digits than its factorization.

21356207021633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29442725.

The product of its (nonzero) digits is 272160, while the sum is 41.

Adding to 21356207021633 its reverse (33612070265312), we get a palindrome (54968277286945).

The spelling of 21356207021633 in words is "twenty-one trillion, three hundred fifty-six billion, two hundred seven million, twenty-one thousand, six hundred thirty-three".