21803850 has 96 divisors (see below), whose sum is σ = 62138880. Its totient is φ = 5616000.

The previous prime is 21803827. The next prime is 21803857. The reversal of 21803850 is 5830812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21803857) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 41590 + ... + 42110.

It is an arithmetic number, because the mean of its divisors is an integer number (647280).

Almost surely, 2^21803850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21803850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31069440).

21803850 is an abundant number, since it is smaller than the sum of its proper divisors (40335030).

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

21803850 is a wasteful number, since it uses less digits than its factorization.

21803850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 573 (or 562 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 21803850 is about 4669.4592834717. The cubic root of 21803850 is about 279.3686882048.

The spelling of 21803850 in words is "twenty-one million, eight hundred three thousand, eight hundred fifty".