21022045 has 16 divisors (see below), whose sum is σ = 27630720. Its totient is φ = 15227200.

The previous prime is 21022021. The next prime is 21022049. The reversal of 21022045 is 54022012.

It is not a de Polignac number, because 21022045 - 2²³ = 12633437 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022049) 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 15 ways as a sum of consecutive naturals, for example, 16491 + ... + 17719.

It is an arithmetic number, because the mean of its divisors is an integer number (1726920).

Almost surely, 2^21022045 is an apocalyptic number.

It is an amenable number.

21022045 is a deficient number, since it is larger than the sum of its proper divisors (6608675).

21022045 is a wasteful number, since it uses less digits than its factorization.

21022045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1556.

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 21022045 is about 4584.9803707322. The cubic root of 21022045 is about 275.9889243263.

Adding to 21022045 its reverse (54022012), we get a palindrome (75044057).

The spelling of 21022045 in words is "twenty-one million, twenty-two thousand, forty-five".