20906833 has 4 divisors (see below), whose sum is σ = 20927088. Its totient is φ = 20886580.

The previous prime is 20906819. The next prime is 20906849. The reversal of 20906833 is 33860902.

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 a cyclic number.

It is not a de Polignac number, because 20906833 - 2⁵ = 20906801 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20906795 and 20906804.

It is not an unprimeable number, because it can be changed into a prime (20906863) 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, 8491 + ... + 10672.

It is an arithmetic number, because the mean of its divisors is an integer number (5231772).

Almost surely, 2^20906833 is an apocalyptic number.

It is an amenable number.

20906833 is a deficient number, since it is larger than the sum of its proper divisors (20255).

20906833 is a wasteful number, since it uses less digits than its factorization.

20906833 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20254.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 20906833 is about 4572.3990420785. The cubic root of 20906833 is about 275.4838116845.

The spelling of 20906833 in words is "twenty million, nine hundred six thousand, eight hundred thirty-three".