21445130 has 16 divisors (see below), whose sum is σ = 44115840. Its totient is φ = 7352592.

The previous prime is 21445121. The next prime is 21445133. The reversal of 21445130 is 3154412.

It is not an unprimeable number, because it can be changed into a prime (21445133) by changing a digit.

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, 153110 + ... + 153249.

It is an arithmetic number, because the mean of its divisors is an integer number (2757240).

Almost surely, 2^21445130 is an apocalyptic number.

21445130 is an abundant number, since it is smaller than the sum of its proper divisors (22670710).

21445130 is a wasteful number, since it uses less digits than its factorization.

21445130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306373.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 21445130 is about 4630.8886836114. Note that the first 3 decimals coincide. The cubic root of 21445130 is about 277.8281376546.

Adding to 21445130 its reverse (3154412), we get a palindrome (24599542).

The spelling of 21445130 in words is "twenty-one million, four hundred forty-five thousand, one hundred thirty".