21133300 has 18 divisors (see below), whose sum is σ = 45859478. Its totient is φ = 8453280.

The previous prime is 21133291. The next prime is 21133303. The reversal of 21133300 is 333112.

It can be written as a sum of positive squares in 3 ways, for example, as 394384 + 20738916 = 628^2 + 4554^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133303) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105567 + ... + 105766.

Almost surely, 2^21133300 is an apocalyptic number.

21133300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21133300 is an abundant number, since it is smaller than the sum of its proper divisors (24726178).

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

21133300 is a wasteful number, since it uses less digits than its factorization.

21133300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211347 (or 211340 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 13.

The square root of 21133300 is about 4597.0969100074. The cubic root of 21133300 is about 276.4749401493.

Adding to 21133300 its reverse (333112), we get a palindrome (21466412).

The spelling of 21133300 in words is "twenty-one million, one hundred thirty-three thousand, three hundred".