21023300 has 18 divisors (see below), whose sum is σ = 45620778. Its totient is φ = 8409280.

The previous prime is 21023287. The next prime is 21023309. The reversal of 21023300 is 332012.

It can be written as a sum of positive squares in 3 ways, for example, as 4393216 + 16630084 = 2096^2 + 4078^2 .

It is not an unprimeable number, because it can be changed into a prime (21023309) 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, 105017 + ... + 105216.

Almost surely, 2^21023300 is an apocalyptic number.

21023300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21023300 is an abundant number, since it is smaller than the sum of its proper divisors (24597478).

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

21023300 is a wasteful number, since it uses less digits than its factorization.

21023300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210247 (or 210240 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 11.

The square root of 21023300 is about 4585.1172285995. The cubic root of 21023300 is about 275.9944163262.

Adding to 21023300 its reverse (332012), we get a palindrome (21355312).

The spelling of 21023300 in words is "twenty-one million, twenty-three thousand, three hundred".