21413633 has 4 divisors (see below), whose sum is σ = 21438768. Its totient is φ = 21388500.

The previous prime is 21413617. The next prime is 21413641. The reversal of 21413633 is 33631412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21413633 - 2⁴ = 21413617 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21413599 and 21413608.

It is not an unprimeable number, because it can be changed into a prime (21413533) 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, 11243 + ... + 13008.

It is an arithmetic number, because the mean of its divisors is an integer number (5359692).

Almost surely, 2^21413633 is an apocalyptic number.

It is an amenable number.

21413633 is a deficient number, since it is larger than the sum of its proper divisors (25135).

21413633 is an equidigital number, since it uses as much as digits as its factorization.

21413633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25134.

The product of its digits is 1296, while the sum is 23.

The square root of 21413633 is about 4627.4866828550. The cubic root of 21413633 is about 277.6920532926.

The spelling of 21413633 in words is "twenty-one million, four hundred thirteen thousand, six hundred thirty-three".