21000300 has 36 divisors (see below), whose sum is σ = 60761736. Its totient is φ = 5600000.

The previous prime is 21000293. The next prime is 21000307. The reversal of 21000300 is 300012.

It is an interprime number because it is at equal distance from previous prime (21000293) and next prime (21000307).

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is not an unprimeable number, because it can be changed into a prime (21000307) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34701 + ... + 35300.

It is an arithmetic number, because the mean of its divisors is an integer number (1687826).

Almost surely, 2^21000300 is an apocalyptic number.

21000300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000300 is an abundant number, since it is smaller than the sum of its proper divisors (39761436).

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

21000300 is a wasteful number, since it uses less digits than its factorization.

21000300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70018 (or 70011 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 6.

The square root of 21000300 is about 4582.6084275225. The cubic root of 21000300 is about 275.8937314053.

Adding to 21000300 its reverse (300012), we get a palindrome (21300312).

The spelling of 21000300 in words is "twenty-one million, three hundred", and thus it is an aban number.