21108067 has 4 divisors (see below), whose sum is σ = 22349736. Its totient is φ = 19866400.

The previous prime is 21108053. The next prime is 21108077. The reversal of 21108067 is 76080112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21108067 - 2²³ = 12719459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21108007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 620809 + ... + 620842.

It is an arithmetic number, because the mean of its divisors is an integer number (5587434).

Almost surely, 2^21108067 is an apocalyptic number.

21108067 is a deficient number, since it is larger than the sum of its proper divisors (1241669).

21108067 is a wasteful number, since it uses less digits than its factorization.

21108067 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1241668.

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 21108067 is about 4594.3516408738. The cubic root of 21108067 is about 276.3648599985.

Adding to 21108067 its reverse (76080112), we get a palindrome (97188179).

The spelling of 21108067 in words is "twenty-one million, one hundred eight thousand, sixty-seven".