21722033 has 4 divisors (see below), whose sum is σ = 21752640. Its totient is φ = 21691428.

The previous prime is 21722021. The next prime is 21722047. The reversal of 21722033 is 33022712.

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 21722033 - 2⁴ = 21722017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21721996 and 21722014.

It is not an unprimeable number, because it can be changed into a prime (21722093) 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, 14213 + ... + 15666.

It is an arithmetic number, because the mean of its divisors is an integer number (5438160).

Almost surely, 2^21722033 is an apocalyptic number.

It is an amenable number.

21722033 is a deficient number, since it is larger than the sum of its proper divisors (30607).

21722033 is an equidigital number, since it uses as much as digits as its factorization.

21722033 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30606.

The product of its (nonzero) digits is 504, while the sum is 20.

The square root of 21722033 is about 4660.6901849404. The cubic root of 21722033 is about 279.0188148649.

Adding to 21722033 its reverse (33022712), we get a palindrome (54744745).

The spelling of 21722033 in words is "twenty-one million, seven hundred twenty-two thousand, thirty-three".