20869818 has 8 divisors (see below), whose sum is σ = 41739648. Its totient is φ = 6956604.

The previous prime is 20869787. The next prime is 20869831. The reversal of 20869818 is 81896802.

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

20869818 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 20869818.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1739146 + ... + 1739157.

It is an arithmetic number, because the mean of its divisors is an integer number (5217456).

Almost surely, 2^20869818 is an apocalyptic number.

20869818 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20869818 is a wasteful number, since it uses less digits than its factorization.

20869818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3478308.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 20869818 is about 4568.3495925772. The cubic root of 20869818 is about 275.3211366860.

The spelling of 20869818 in words is "twenty million, eight hundred sixty-nine thousand, eight hundred eighteen".