21203000 has 128 divisors (see below), whose sum is σ = 61326720. Its totient is φ = 6681600.

The previous prime is 21202997. The next prime is 21203003. The reversal of 21203000 is 30212.

It is an interprime number because it is at equal distance from previous prime (21202997) and next prime (21203003).

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203003) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 90884 + ... + 91116.

It is an arithmetic number, because the mean of its divisors is an integer number (479115).

Almost surely, 2^21203000 is an apocalyptic number.

21203000 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 21203000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30663360).

21203000 is an abundant number, since it is smaller than the sum of its proper divisors (40123720).

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

21203000 is a wasteful number, since it uses less digits than its factorization.

21203000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 260 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 8.

The square root of 21203000 is about 4604.6715409462. The cubic root of 21203000 is about 276.7785550896.

Adding to 21203000 its reverse (30212), we get a palindrome (21233212).

The spelling of 21203000 in words is "twenty-one million, two hundred three thousand".