21853827 has 8 divisors (see below), whose sum is σ = 32376080. Its totient is φ = 14569200.

The previous prime is 21853807. The next prime is 21853831. The reversal of 21853827 is 72835812.

It is not a de Polignac number, because 21853827 - 2⁶ = 21853763 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21853791 and 21853800.

It is not an unprimeable number, because it can be changed into a prime (21853807) 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, 404674 + ... + 404727.

It is an arithmetic number, because the mean of its divisors is an integer number (4047010).

Almost surely, 2^21853827 is an apocalyptic number.

21853827 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21853827 is a deficient number, since it is larger than the sum of its proper divisors (10522253).

21853827 is an equidigital number, since it uses as much as digits as its factorization.

21853827 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 809410 (or 809404 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 21853827 is about 4674.8076965796. The cubic root of 21853827 is about 279.5819740078.

It can be divided in two parts, 218 and 53827, that added together give a palindrome (54045).

The spelling of 21853827 in words is "twenty-one million, eight hundred fifty-three thousand, eight hundred twenty-seven".