21442065 has 16 divisors (see below), whose sum is σ = 34424448. Its totient is φ = 11396736.

The previous prime is 21442063. The next prime is 21442067. The reversal of 21442065 is 56024412.

It is an interprime number because it is at equal distance from previous prime (21442063) and next prime (21442067).

It is not a de Polignac number, because 21442065 - 2¹ = 21442063 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21442063) 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, 2412 + ... + 6978.

It is an arithmetic number, because the mean of its divisors is an integer number (2151528).

Almost surely, 2^21442065 is an apocalyptic number.

It is an amenable number.

21442065 is a deficient number, since it is larger than the sum of its proper divisors (12982383).

21442065 is a wasteful number, since it uses less digits than its factorization.

21442065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4888.

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 21442065 is about 4630.5577417845. The cubic root of 21442065 is about 277.8149010237.

Adding to 21442065 its reverse (56024412), we get a palindrome (77466477).

The spelling of 21442065 in words is "twenty-one million, four hundred forty-two thousand, sixty-five".