21523362 has 64 divisors (see below), whose sum is σ = 51806208. Its totient is φ = 5832000.

The previous prime is 21523361. The next prime is 21523387. The reversal of 21523362 is 26332512.

It is a super-2 number, since 2×21523362² = 926510223566088, which contains 22 as substring.

It is a plaindrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (21523361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 79287 + ... + 79557.

It is an arithmetic number, because the mean of its divisors is an integer number (809472).

Almost surely, 2^21523362 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21523362, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25903104).

21523362 is an abundant number, since it is smaller than the sum of its proper divisors (30282846).

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

21523362 is a wasteful number, since it uses less digits than its factorization.

21523362 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375.

The product of its digits is 2160, while the sum is 24.

The square root of 21523362 is about 4639.3277530263. The cubic root of 21523362 is about 278.1655674024.

Adding to 21523362 its reverse (26332512), we get a palindrome (47855874).

The spelling of 21523362 in words is "twenty-one million, five hundred twenty-three thousand, three hundred sixty-two".