20889911 has 16 divisors (see below), whose sum is σ = 26227200. Its totient is φ = 16223328.

The previous prime is 20889901. The next prime is 20889929. The reversal of 20889911 is 11998802.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20889911 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 (20889901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 356 + ... + 6473.

It is an arithmetic number, because the mean of its divisors is an integer number (1639200).

Almost surely, 2^20889911 is an apocalyptic number.

20889911 is a deficient number, since it is larger than the sum of its proper divisors (5337289).

20889911 is a wasteful number, since it uses less digits than its factorization.

20889911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6878.

The product of its (nonzero) digits is 10368, while the sum is 38.

The square root of 20889911 is about 4570.5482165710. The cubic root of 20889911 is about 275.4094660488.

The spelling of 20889911 in words is "twenty million, eight hundred eighty-nine thousand, nine hundred eleven".