21998834 has 16 divisors (see below), whose sum is σ = 38767680. Its totient is φ = 9230160.

The previous prime is 21998819. The next prime is 21998839. The reversal of 21998834 is 43889912.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21998839) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38174 + ... + 38745.

It is an arithmetic number, because the mean of its divisors is an integer number (2422980).

Almost surely, 2^21998834 is an apocalyptic number.

21998834 is a deficient number, since it is larger than the sum of its proper divisors (16768846).

21998834 is a wasteful number, since it uses less digits than its factorization.

21998834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76945.

The product of its digits is 124416, while the sum is 44.

The square root of 21998834 is about 4690.2914621588. The cubic root of 21998834 is about 280.1989827086.

It can be divided in two parts, 219988 and 34, that added together give a palindrome (220022).

The spelling of 21998834 in words is "twenty-one million, nine hundred ninety-eight thousand, eight hundred thirty-four".