21442733 has 8 divisors (see below), whose sum is σ = 23385600. Its totient is φ = 19541808.

The previous prime is 21442717. The next prime is 21442741. The reversal of 21442733 is 33724412.

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

It is not a de Polignac number, because 21442733 - 2⁴ = 21442717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442703) 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, 9413 + ... + 11466.

It is an arithmetic number, because the mean of its divisors is an integer number (2923200).

Almost surely, 2^21442733 is an apocalyptic number.

It is an amenable number.

21442733 is a deficient number, since it is larger than the sum of its proper divisors (1942867).

21442733 is a wasteful number, since it uses less digits than its factorization.

21442733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20971.

The product of its digits is 4032, while the sum is 26.

The square root of 21442733 is about 4630.6298707627. The cubic root of 21442733 is about 277.8177859825.

The spelling of 21442733 in words is "twenty-one million, four hundred forty-two thousand, seven hundred thirty-three".