21440200 has 24 divisors (see below), whose sum is σ = 49848930. Its totient is φ = 8576000.

The previous prime is 21440183. The next prime is 21440203. The reversal of 21440200 is 204412.

It can be written as a sum of positive squares in 3 ways, for example, as 10510564 + 10929636 = 3242^2 + 3306^2 .

It is a super-3 number, since 3×21440200³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440203) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 53401 + ... + 53800.

Almost surely, 2^21440200 is an apocalyptic number.

21440200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21440200 is an abundant number, since it is smaller than the sum of its proper divisors (28408730).

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

21440200 is a wasteful number, since it uses less digits than its factorization.

21440200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107217 (or 107208 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 21440200 is about 4630.3563577764. The cubic root of 21440200 is about 277.8068461432.

Adding to 21440200 its reverse (204412), we get a palindrome (21644612).

The spelling of 21440200 in words is "twenty-one million, four hundred forty thousand, two hundred".