21998854 has 4 divisors (see below), whose sum is σ = 32998284. Its totient is φ = 10999426.

The previous prime is 21998839. The next prime is 21998863. The reversal of 21998854 is 45889912.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5499712 + ... + 5499715.

It is an arithmetic number, because the mean of its divisors is an integer number (8249571).

Almost surely, 2^21998854 is an apocalyptic number.

21998854 is a deficient number, since it is larger than the sum of its proper divisors (10999430).

21998854 is a wasteful number, since it uses less digits than its factorization.

21998854 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10999429.

The product of its digits is 207360, while the sum is 46.

The square root of 21998854 is about 4690.2935942220. The cubic root of 21998854 is about 280.1990676219.

The spelling of 21998854 in words is "twenty-one million, nine hundred ninety-eight thousand, eight hundred fifty-four".