20133921 has 4 divisors (see below), whose sum is σ = 26845232. Its totient is φ = 13422612.

The previous prime is 20133889. The next prime is 20133937. The reversal of 20133921 is 12933102.

It is a happy number.

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 not a de Polignac number, because 20133921 - 2⁵ = 20133889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20133961) 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, 3355651 + ... + 3355656.

It is an arithmetic number, because the mean of its divisors is an integer number (6711308).

Almost surely, 2^20133921 is an apocalyptic number.

It is an amenable number.

20133921 is a deficient number, since it is larger than the sum of its proper divisors (6711311).

20133921 is an equidigital number, since it uses as much as digits as its factorization.

20133921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6711310.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 20133921 is about 4487.0837968551. The cubic root of 20133921 is about 272.0462769085.

The spelling of 20133921 in words is "twenty million, one hundred thirty-three thousand, nine hundred twenty-one".