21828586 has 16 divisors (see below), whose sum is σ = 36013824. Its totient is φ = 9859824.

The previous prime is 21828581. The next prime is 21828593. The reversal of 21828586 is 68582812.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21828581) 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, 7710 + ... + 10153.

It is an arithmetic number, because the mean of its divisors is an integer number (2250864).

Almost surely, 2^21828586 is an apocalyptic number.

21828586 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21828586 is a deficient number, since it is larger than the sum of its proper divisors (14185238).

21828586 is a wasteful number, since it uses less digits than its factorization.

21828586 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17925.

The product of its digits is 61440, while the sum is 40.

The square root of 21828586 is about 4672.1072333584. The cubic root of 21828586 is about 279.4742942065.

The spelling of 21828586 in words is "twenty-one million, eight hundred twenty-eight thousand, five hundred eighty-six".