21030430 has 32 divisors (see below), whose sum is σ = 39299904. Its totient is φ = 8096256.

The previous prime is 21030403. The next prime is 21030463. The reversal of 21030430 is 3403012.

It is a self number, because there is not a number n which added to its sum of digits gives 21030430.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 41559 + ... + 42061.

It is an arithmetic number, because the mean of its divisors is an integer number (1228122).

Almost surely, 2^21030430 is an apocalyptic number.

21030430 is a deficient number, since it is larger than the sum of its proper divisors (18269474).

21030430 is a wasteful number, since it uses less digits than its factorization.

21030430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660.

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 21030430 is about 4585.8946782498. The cubic root of 21030430 is about 276.0256137399.

Adding to 21030430 its reverse (3403012), we get a palindrome (24433442).

The spelling of 21030430 in words is "twenty-one million, thirty thousand, four hundred thirty".