21426336 has 48 divisors (see below), whose sum is σ = 62496000. Its totient is φ = 7141824.

The previous prime is 21426329. The next prime is 21426337. The reversal of 21426336 is 63362412.

21426336 is a `hidden beast` number, since 21 + 4 + 2 + 633 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

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

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21426337) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11536 + ... + 13263.

It is an arithmetic number, because the mean of its divisors is an integer number (1302000).

Almost surely, 2^21426336 is an apocalyptic number.

It is an amenable number.

21426336 is an abundant number, since it is smaller than the sum of its proper divisors (41069664).

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

21426336 is a wasteful number, since it uses less digits than its factorization.

21426336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24818 (or 24804 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

The square root of 21426336 is about 4628.8590386833. The cubic root of 21426336 is about 277.7469532848.

Adding to 21426336 its reverse (63362412), we get a palindrome (84788748).

The spelling of 21426336 in words is "twenty-one million, four hundred twenty-six thousand, three hundred thirty-six".