21998600 has 48 divisors (see below), whose sum is σ = 55087620. Its totient is φ = 8121600.

The previous prime is 21998597. The next prime is 21998621. The reversal of 21998600 is 689912.

It can be written as a sum of positive squares in 6 ways, for example, as 7695076 + 14303524 = 2774^2 + 3782^2 .

It is an unprimeable number.

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, 1631 + ... + 6830.

Almost surely, 2^21998600 is an apocalyptic number.

21998600 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21998600 is an abundant number, since it is smaller than the sum of its proper divisors (33089020).

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

21998600 is a wasteful number, since it uses less digits than its factorization.

21998600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8490 (or 8481 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 21998600 is about 4690.2665169476. The cubic root of 21998600 is about 280.1979892197.

The spelling of 21998600 in words is "twenty-one million, nine hundred ninety-eight thousand, six hundred".