21022300 has 72 divisors (see below), whose sum is σ = 49920416. Its totient is φ = 7637760.

The previous prime is 21022279. The next prime is 21022357. The reversal of 21022300 is 322012.

It is a super-4 number, since 4×21022300⁴ (a number of 30 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 133822 + ... + 133978.

Almost surely, 2^21022300 is an apocalyptic number.

21022300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21022300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24960208).

21022300 is an abundant number, since it is smaller than the sum of its proper divisors (28898116).

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

21022300 is a wasteful number, since it uses less digits than its factorization.

21022300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 21022300 is about 4585.0081788368. The cubic root of 21022300 is about 275.9900402483.

Adding to 21022300 its reverse (322012), we get a palindrome (21344312).

The spelling of 21022300 in words is "twenty-one million, twenty-two thousand, three hundred".