20864789 has 8 divisors (see below), whose sum is σ = 23036832. Its totient is φ = 18738640.

The previous prime is 20864783. The next prime is 20864791. The reversal of 20864789 is 98746802.

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

It is a cyclic number.

It is not a de Polignac number, because 20864789 - 2⁴ = 20864773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20864783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10514 + ... + 12339.

It is an arithmetic number, because the mean of its divisors is an integer number (2879604).

Almost surely, 2^20864789 is an apocalyptic number.

It is an amenable number.

20864789 is a deficient number, since it is larger than the sum of its proper divisors (2172043).

20864789 is a wasteful number, since it uses less digits than its factorization.

20864789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22947.

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 20864789 is about 4567.7991418187. The cubic root of 20864789 is about 275.2990201982.

The spelling of 20864789 in words is "twenty million, eight hundred sixty-four thousand, seven hundred eighty-nine".