20890863 has 24 divisors (see below), whose sum is σ = 34664448. Its totient is φ = 11876112.

The previous prime is 20890813. The next prime is 20890867. The reversal of 20890863 is 36809802.

It is not a de Polignac number, because 20890863 - 2⁶ = 20890799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20890867) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13306 + ... + 14792.

It is an arithmetic number, because the mean of its divisors is an integer number (1444352).

Almost surely, 2^20890863 is an apocalyptic number.

20890863 is a deficient number, since it is larger than the sum of its proper divisors (13773585).

20890863 is a wasteful number, since it uses less digits than its factorization.

20890863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1723 (or 1720 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 20890863 is about 4570.6523604405. The cubic root of 20890863 is about 275.4136496606.

The spelling of 20890863 in words is "twenty million, eight hundred ninety thousand, eight hundred sixty-three".