21055633 has 8 divisors (see below), whose sum is σ = 21415680. Its totient is φ = 20698080.

The previous prime is 21055631. The next prime is 21055663. The reversal of 21055633 is 33655012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21055633 - 2¹ = 21055631 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21055598 and 21055607.

It is not an unprimeable number, because it can be changed into a prime (21055631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24141 + ... + 24997.

It is an arithmetic number, because the mean of its divisors is an integer number (2676960).

Almost surely, 2^21055633 is an apocalyptic number.

It is an amenable number.

21055633 is a deficient number, since it is larger than the sum of its proper divisors (360047).

21055633 is an equidigital number, since it uses as much as digits as its factorization.

21055633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247.

The product of its (nonzero) digits is 2700, while the sum is 25.

The square root of 21055633 is about 4588.6417380310. The cubic root of 21055633 is about 276.1358333347.

The spelling of 21055633 in words is "twenty-one million, fifty-five thousand, six hundred thirty-three".