21442167 has 6 divisors (see below), whose sum is σ = 30972032. Its totient is φ = 14294772.

The previous prime is 21442163. The next prime is 21442229. The reversal of 21442167 is 76124412.

It is not a de Polignac number, because 21442167 - 2² = 21442163 is a prime.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a nialpdrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 21442167.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21442163) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1191223 + ... + 1191240.

Almost surely, 2^21442167 is an apocalyptic number.

21442167 is a deficient number, since it is larger than the sum of its proper divisors (9529865).

21442167 is a wasteful number, since it uses less digits than its factorization.

21442167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2382469 (or 2382466 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 21442167 is about 4630.5687555634. The cubic root of 21442167 is about 277.8153415452.

Adding to 21442167 its reverse (76124412), we get a palindrome (97566579).

It can be divided in two parts, 21442 and 167, that added together give a square (21609 = 147²).

The spelling of 21442167 in words is "twenty-one million, four hundred forty-two thousand, one hundred sixty-seven".