20333721 has 8 divisors (see below), whose sum is σ = 27262144. Its totient is φ = 13480560.

The previous prime is 20333713. The next prime is 20333759. The reversal of 20333721 is 12733302.

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

It is not a de Polignac number, because 20333721 - 2³ = 20333713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20333791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18181 + ... + 19266.

It is an arithmetic number, because the mean of its divisors is an integer number (3407768).

Almost surely, 2^20333721 is an apocalyptic number.

It is an amenable number.

20333721 is a deficient number, since it is larger than the sum of its proper divisors (6928423).

20333721 is a wasteful number, since it uses less digits than its factorization.

20333721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37631.

The product of its (nonzero) digits is 756, while the sum is 21.

The square root of 20333721 is about 4509.2927383349. The cubic root of 20333721 is about 272.9432049196.

The spelling of 20333721 in words is "twenty million, three hundred thirty-three thousand, seven hundred twenty-one".