21803853 has 8 divisors (see below), whose sum is σ = 30074400. Its totient is φ = 14034608.

The previous prime is 21803827. The next prime is 21803857. The reversal of 21803853 is 35830812.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21803853 - 2¹³ = 21795661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21803853.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 125223 + ... + 125396.

It is an arithmetic number, because the mean of its divisors is an integer number (3759300).

Almost surely, 2^21803853 is an apocalyptic number.

It is an amenable number.

21803853 is a deficient number, since it is larger than the sum of its proper divisors (8270547).

21803853 is a wasteful number, since it uses less digits than its factorization.

21803853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250651.

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 21803853 is about 4669.4596047080. The cubic root of 21803853 is about 279.3687010176.

The spelling of 21803853 in words is "twenty-one million, eight hundred three thousand, eight hundred fifty-three".