21234730 has 16 divisors (see below), whose sum is σ = 41697504. Its totient is φ = 7721680.

The previous prime is 21234713. The next prime is 21234767. The reversal of 21234730 is 3743212.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96412 + ... + 96631.

It is an arithmetic number, because the mean of its divisors is an integer number (2606094).

Almost surely, 2^21234730 is an apocalyptic number.

21234730 is a deficient number, since it is larger than the sum of its proper divisors (20462774).

21234730 is a wasteful number, since it uses less digits than its factorization.

21234730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193061.

The product of its (nonzero) digits is 1008, while the sum is 22.

The square root of 21234730 is about 4608.1156669511. The cubic root of 21234730 is about 276.9165513855.

Adding to 21234730 its reverse (3743212), we get a palindrome (24977942).

The spelling of 21234730 in words is "twenty-one million, two hundred thirty-four thousand, seven hundred thirty".