21345430 has 16 divisors (see below), whose sum is σ = 38782800. Its totient is φ = 8457952.

The previous prime is 21345427. The next prime is 21345431. The reversal of 21345430 is 3454312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8905 + ... + 11044.

It is an arithmetic number, because the mean of its divisors is an integer number (2423925).

Almost surely, 2^21345430 is an apocalyptic number.

21345430 is a deficient number, since it is larger than the sum of its proper divisors (17437370).

21345430 is a wasteful number, since it uses less digits than its factorization.

21345430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20063.

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 21345430 is about 4620.1114705167. Note that the first 3 decimals coincide. The cubic root of 21345430 is about 277.3969208366.

Adding to 21345430 its reverse (3454312), we get a palindrome (24799742).

The spelling of 21345430 in words is "twenty-one million, three hundred forty-five thousand, four hundred thirty".