21816273 has 8 divisors (see below), whose sum is σ = 29874688. Its totient is φ = 14151024.

The previous prime is 21816271. The next prime is 21816293. The reversal of 21816273 is 37261812.

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

It is not a de Polignac number, because 21816273 - 2¹ = 21816271 is a prime.

It is a super-2 number, since 2×21816273² = 951899535221058, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21816273.

It is not an unprimeable number, because it can be changed into a prime (21816271) 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, 98161 + ... + 98382.

It is an arithmetic number, because the mean of its divisors is an integer number (3734336).

Almost surely, 2^21816273 is an apocalyptic number.

It is an amenable number.

21816273 is a deficient number, since it is larger than the sum of its proper divisors (8058415).

21816273 is a wasteful number, since it uses less digits than its factorization.

21816273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196583.

The product of its digits is 4032, while the sum is 30.

The square root of 21816273 is about 4670.7893337208. The cubic root of 21816273 is about 279.4217359966.

The spelling of 21816273 in words is "twenty-one million, eight hundred sixteen thousand, two hundred seventy-three".