21870200 has 48 divisors (see below), whose sum is σ = 55476360. Its totient is φ = 7952000.

The previous prime is 21870193. The next prime is 21870209. The reversal of 21870200 is 207812.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21870209) 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, 2771 + ... + 7170.

Almost surely, 2^21870200 is an apocalyptic number.

21870200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21870200 is an abundant number, since it is smaller than the sum of its proper divisors (33606160).

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

21870200 is a wasteful number, since it uses less digits than its factorization.

21870200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9968 (or 9959 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 21870200 is about 4676.5585637304. The cubic root of 21870200 is about 279.6517779976.

The spelling of 21870200 in words is "twenty-one million, eight hundred seventy thousand, two hundred".