21421200 has 60 divisors (see below), whose sum is σ = 68623088. Its totient is φ = 5712000.

The previous prime is 21421177. The next prime is 21421201. The reversal of 21421200 is 212412.

21421200 = T₃₁₉ + T₃₂₀ + ... + T₅₄₃.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21421201) 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 11 ways as a sum of consecutive naturals, for example, 7726 + ... + 10125.

Almost surely, 2^21421200 is an apocalyptic number.

21421200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21421200 is an abundant number, since it is smaller than the sum of its proper divisors (47201888).

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

21421200 is a wasteful number, since it uses less digits than its factorization.

21421200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17872 (or 17861 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21421200 is about 4628.3042250915. The cubic root of 21421200 is about 277.7247590663.

Adding to 21421200 its reverse (212412), we get a palindrome (21633612).

The spelling of 21421200 in words is "twenty-one million, four hundred twenty-one thousand, two hundred".