21003330 has 32 divisors (see below), whose sum is σ = 53374464. Its totient is φ = 5271296.

The previous prime is 21003329. The next prime is 21003331. The reversal of 21003330 is 3330012.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21003329) and next prime (21003331).

It is a super-2 number, since 2×21003330² = 882279742177800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21003331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20082 + ... + 21101.

It is an arithmetic number, because the mean of its divisors is an integer number (1667952).

Almost surely, 2^21003330 is an apocalyptic number.

21003330 is an abundant number, since it is smaller than the sum of its proper divisors (32371134).

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

21003330 is a wasteful number, since it uses less digits than its factorization.

21003330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41210.

The product of its (nonzero) digits is 54, while the sum is 12.

The square root of 21003330 is about 4582.9390133407. The cubic root of 21003330 is about 275.9069997523.

Adding to 21003330 its reverse (3330012), we get a palindrome (24333342).

The spelling of 21003330 in words is "twenty-one million, three thousand, three hundred thirty".