21428300 has 18 divisors (see below), whose sum is σ = 46499628. Its totient is φ = 8571280.

The previous prime is 21428243. The next prime is 21428317. The reversal of 21428300 is 382412.

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

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 107042 + ... + 107241.

Almost surely, 2^21428300 is an apocalyptic number.

21428300 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21428300 is an abundant number, since it is smaller than the sum of its proper divisors (25071328).

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

21428300 is a wasteful number, since it uses less digits than its factorization.

21428300 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214297 (or 214290 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 21428300 is about 4629.0711811334. The cubic root of 21428300 is about 277.7554393888.

The spelling of 21428300 in words is "twenty-one million, four hundred twenty-eight thousand, three hundred".