21969800 has 24 divisors (see below), whose sum is σ = 51080250. Its totient is φ = 8787840.

The previous prime is 21969781. The next prime is 21969811. The reversal of 21969800 is 896912.

It can be written as a sum of positive squares in 3 ways, for example, as 11303044 + 10666756 = 3362^2 + 3266^2 .

It is a super-2 number, since 2×21969800² = 965344224080000, which contains 22 as substring.

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 in 5 ways as a sum of consecutive naturals, for example, 54725 + ... + 55124.

Almost surely, 2^21969800 is an apocalyptic number.

21969800 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21969800 is an abundant number, since it is smaller than the sum of its proper divisors (29110450).

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

21969800 is a wasteful number, since it uses less digits than its factorization.

21969800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109865 (or 109856 counting only the distinct ones).

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

The square root of 21969800 is about 4687.1953234317. The cubic root of 21969800 is about 280.0756598259.

The spelling of 21969800 in words is "twenty-one million, nine hundred sixty-nine thousand, eight hundred".