21536226 has 16 divisors (see below), whose sum is σ = 47858400. Its totient is φ = 7178724.

The previous prime is 21536213. The next prime is 21536261. The reversal of 21536226 is 62263512.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21536226.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 199356 + ... + 199463.

It is an arithmetic number, because the mean of its divisors is an integer number (2991150).

Almost surely, 2^21536226 is an apocalyptic number.

21536226 is an abundant number, since it is smaller than the sum of its proper divisors (26322174).

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

21536226 is a wasteful number, since it uses less digits than its factorization.

21536226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398830 (or 398824 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 21536226 is about 4640.7139536929. The cubic root of 21536226 is about 278.2209740067.

Adding to 21536226 its reverse (62263512), we get a palindrome (83799738).

The spelling of 21536226 in words is "twenty-one million, five hundred thirty-six thousand, two hundred twenty-six".