21104297 has 4 divisors (see below), whose sum is σ = 21371520. Its totient is φ = 20837076.

The previous prime is 21104287. The next prime is 21104311. The reversal of 21104297 is 79240112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21104297 - 2⁶ = 21104233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21104267) 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, 133493 + ... + 133650.

It is an arithmetic number, because the mean of its divisors is an integer number (5342880).

Almost surely, 2^21104297 is an apocalyptic number.

It is an amenable number.

21104297 is a deficient number, since it is larger than the sum of its proper divisors (267223).

21104297 is an equidigital number, since it uses as much as digits as its factorization.

21104297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267222.

The product of its (nonzero) digits is 1008, while the sum is 26.

The square root of 21104297 is about 4593.9413361513. The cubic root of 21104297 is about 276.3484056644.

The spelling of 21104297 in words is "twenty-one million, one hundred four thousand, two hundred ninety-seven".