21069330 has 16 divisors (see below), whose sum is σ = 50566464. Its totient is φ = 5618480.

The previous prime is 21069319. The next prime is 21069343. The reversal of 21069330 is 3396012.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21069330.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 351126 + ... + 351185.

It is an arithmetic number, because the mean of its divisors is an integer number (3160404).

Almost surely, 2^21069330 is an apocalyptic number.

21069330 is an abundant number, since it is smaller than the sum of its proper divisors (29497134).

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

21069330 is a wasteful number, since it uses less digits than its factorization.

21069330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702321.

The product of its (nonzero) digits is 972, while the sum is 24.

The square root of 21069330 is about 4590.1339849726. The cubic root of 21069330 is about 276.1956971674.

It can be divided in two parts, 210693 and 30, that multiplied together give a triangular number (6320790 = T₃₅₅₅).

The spelling of 21069330 in words is "twenty-one million, sixty-nine thousand, three hundred thirty".