21104017 has 12 divisors (see below), whose sum is σ = 23499504. Its totient is φ = 18795920.

The previous prime is 21104011. The next prime is 21104029. The reversal of 21104017 is 71040112.

It is not a de Polignac number, because 21104017 - 2¹⁵ = 21071249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21104011) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30558 + ... + 31240.

It is an arithmetic number, because the mean of its divisors is an integer number (1958292).

Almost surely, 2^21104017 is an apocalyptic number.

It is an amenable number.

21104017 is a deficient number, since it is larger than the sum of its proper divisors (2395487).

21104017 is an equidigital number, since it uses as much as digits as its factorization.

21104017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800 (or 747 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 16.

The square root of 21104017 is about 4593.9108611291. The cubic root of 21104017 is about 276.3471835137.

Adding to 21104017 its reverse (71040112), we get a palindrome (92144129).

The spelling of 21104017 in words is "twenty-one million, one hundred four thousand, seventeen".