20673845 has 4 divisors (see below), whose sum is σ = 24808620. Its totient is φ = 16539072.

The previous prime is 20673823. The next prime is 20673859. The reversal of 20673845 is 54837602.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12229009 + 8444836 = 3497^2 + 2906^2 .

It is a cyclic number.

It is not a de Polignac number, because 20673845 - 2²⁰ = 19625269 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2067380 + ... + 2067389.

It is an arithmetic number, because the mean of its divisors is an integer number (6202155).

Almost surely, 2^20673845 is an apocalyptic number.

It is an amenable number.

20673845 is a deficient number, since it is larger than the sum of its proper divisors (4134775).

20673845 is an equidigital number, since it uses as much as digits as its factorization.

20673845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4134774.

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 20673845 is about 4546.8500085224. The cubic root of 20673845 is about 274.4566461393.

The spelling of 20673845 in words is "twenty million, six hundred seventy-three thousand, eight hundred forty-five".