21680095 has 4 divisors (see below), whose sum is σ = 26016120. Its totient is φ = 17344072.

The previous prime is 21680093. The next prime is 21680101. The reversal of 21680095 is 59008612.

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 21680095 - 2¹ = 21680093 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21680093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2168005 + ... + 2168014.

It is an arithmetic number, because the mean of its divisors is an integer number (6504030).

Almost surely, 2^21680095 is an apocalyptic number.

21680095 is a deficient number, since it is larger than the sum of its proper divisors (4336025).

21680095 is an equidigital number, since it uses as much as digits as its factorization.

21680095 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4336024.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 21680095 is about 4656.1888922165. The cubic root of 21680095 is about 278.8391350945.

The spelling of 21680095 in words is "twenty-one million, six hundred eighty thousand, ninety-five".