21140445 has 16 divisors (see below), whose sum is σ = 35605440. Its totient is φ = 10681344.

The previous prime is 21140423. The next prime is 21140501. The reversal of 21140445 is 54404112.

It is a happy number.

It is not a de Polignac number, because 21140445 - 2²¹ = 19043293 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36804 + ... + 37373.

It is an arithmetic number, because the mean of its divisors is an integer number (2225340).

Almost surely, 2^21140445 is an apocalyptic number.

It is an amenable number.

21140445 is a deficient number, since it is larger than the sum of its proper divisors (14464995).

21140445 is a wasteful number, since it uses less digits than its factorization.

21140445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74204.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 21140445 is about 4597.8739652148. The cubic root of 21140445 is about 276.5060946285.

Adding to 21140445 its reverse (54404112), we get a palindrome (75544557).

The spelling of 21140445 in words is "twenty-one million, one hundred forty thousand, four hundred forty-five".