21120330 has 128 divisors (see below), whose sum is σ = 65028096. Its totient is φ = 4262400.

The previous prime is 21120317. The next prime is 21120349. The reversal of 21120330 is 3302112.

It is a happy number.

It is a super-3 number, since 3×21120330³ (a number of 23 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 94599 + ... + 94821.

It is an arithmetic number, because the mean of its divisors is an integer number (508032).

Almost surely, 2^21120330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21120330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32514048).

21120330 is an abundant number, since it is smaller than the sum of its proper divisors (43907766).

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

21120330 is a wasteful number, since it uses less digits than its factorization.

21120330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 21120330 is about 4595.6860206067. The cubic root of 21120330 is about 276.4183688645.

Adding to 21120330 its reverse (3302112), we get a palindrome (24422442).

It can be divided in two parts, 21120 and 330, that multiplied together give a square (6969600 = 2640²).

The spelling of 21120330 in words is "twenty-one million, one hundred twenty thousand, three hundred thirty".