20872823 has 4 divisors (see below), whose sum is σ = 20913408. Its totient is φ = 20832240.

The previous prime is 20872807. The next prime is 20872853. The reversal of 20872823 is 32827802.

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

It is a cyclic number.

It is not a de Polignac number, because 20872823 - 2⁴ = 20872807 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20872823.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20872853) 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, 19511 + ... + 20552.

It is an arithmetic number, because the mean of its divisors is an integer number (5228352).

Almost surely, 2^20872823 is an apocalyptic number.

20872823 is a deficient number, since it is larger than the sum of its proper divisors (40585).

20872823 is an equidigital number, since it uses as much as digits as its factorization.

20872823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40584.

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 20872823 is about 4568.6784741323. The cubic root of 20872823 is about 275.3343503504.

The spelling of 20872823 in words is "twenty million, eight hundred seventy-two thousand, eight hundred twenty-three".