21334530 has 64 divisors (see below), whose sum is σ = 61608960. Its totient is φ = 4618944.

The previous prime is 21334499. The next prime is 21334559. The reversal of 21334530 is 3543312.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 21334497 and 21334506.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1317 + ... + 6663.

It is an arithmetic number, because the mean of its divisors is an integer number (962640).

Almost surely, 2^21334530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21334530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30804480).

21334530 is an abundant number, since it is smaller than the sum of its proper divisors (40274430).

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

21334530 is a wasteful number, since it uses less digits than its factorization.

21334530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5383.

The product of its (nonzero) digits is 1080, while the sum is 21.

The square root of 21334530 is about 4618.9316946671. The cubic root of 21334530 is about 277.3496954078.

Adding to 21334530 its reverse (3543312), we get a palindrome (24877842).

It can be divided in two parts, 213 and 34530, that added together give a palindrome (34743).

The spelling of 21334530 in words is "twenty-one million, three hundred thirty-four thousand, five hundred thirty".