21873330 has 48 divisors (see below), whose sum is σ = 58091904. Its totient is φ = 5707680.

The previous prime is 21873311. The next prime is 21873331. The reversal of 21873330 is 3337812.

It is a junction number, because it is equal to n+sod(n) for n = 21873294 and 21873303.

It is not an unprimeable number, because it can be changed into a prime (21873331) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1645 + ... + 6815.

It is an arithmetic number, because the mean of its divisors is an integer number (1210248).

Almost surely, 2^21873330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21873330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29045952).

21873330 is an abundant number, since it is smaller than the sum of its proper divisors (36218574).

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

21873330 is a wasteful number, since it uses less digits than its factorization.

21873330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5231 (or 5228 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 21873330 is about 4676.8931995503. The cubic root of 21873330 is about 279.6651183467.

The spelling of 21873330 in words is "twenty-one million, eight hundred seventy-three thousand, three hundred thirty".