21804107 has 8 divisors (see below), whose sum is σ = 23595600. Its totient is φ = 20028960.

The previous prime is 21804091. The next prime is 21804109. The reversal of 21804107 is 70140812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21804107 - 2⁴ = 21804091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21804109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1232 + ... + 6717.

It is an arithmetic number, because the mean of its divisors is an integer number (2949450).

Almost surely, 2^21804107 is an apocalyptic number.

21804107 is a deficient number, since it is larger than the sum of its proper divisors (1791493).

21804107 is a wasteful number, since it uses less digits than its factorization.

21804107 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8173.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 21804107 is about 4669.4868026369. The cubic root of 21804107 is about 279.3697858316.

Adding to 21804107 its reverse (70140812), we get a palindrome (91944919).

The spelling of 21804107 in words is "twenty-one million, eight hundred four thousand, one hundred seven".