20989854 has 24 divisors (see below), whose sum is σ = 47163480. Its totient is φ = 6996456.

The previous prime is 20989853. The next prime is 20989861. The reversal of 20989854 is 45898902.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20989853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21109 + ... + 22080.

It is an arithmetic number, because the mean of its divisors is an integer number (1965145).

Almost surely, 2^20989854 is an apocalyptic number.

20989854 is an abundant number, since it is smaller than the sum of its proper divisors (26173626).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20989854 is an equidigital number, since it uses as much as digits as its factorization.

20989854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43206 (or 43194 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 20989854 is about 4581.4685418542. The cubic root of 20989854 is about 275.8479786636.

The spelling of 20989854 in words is "twenty million, nine hundred eighty-nine thousand, eight hundred fifty-four".