21220430 has 96 divisors (see below), whose sum is σ = 50429952. Its totient is φ = 6350400.

The previous prime is 21220429. The next prime is 21220477. The reversal of 21220430 is 3402212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 167027 + ... + 167153.

It is an arithmetic number, because the mean of its divisors is an integer number (525312).

Almost surely, 2^21220430 is an apocalyptic number.

21220430 is an abundant number, since it is smaller than the sum of its proper divisors (29209522).

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

21220430 is a wasteful number, since it uses less digits than its factorization.

21220430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21220430 is about 4606.5637952817. The cubic root of 21220430 is about 276.8543765754.

Adding to 21220430 its reverse (3402212), we get a palindrome (24622642).

The spelling of 21220430 in words is "twenty-one million, two hundred twenty thousand, four hundred thirty".