21449217 has 8 divisors (see below), whose sum is σ = 29264224. Its totient is φ = 13966848.

The previous prime is 21449213. The next prime is 21449221. The reversal of 21449217 is 71294412.

It is an interprime number because it is at equal distance from previous prime (21449213) and next prime (21449221).

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

It is not a de Polignac number, because 21449217 - 2² = 21449213 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21449213) 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, 83008 + ... + 83265.

It is an arithmetic number, because the mean of its divisors is an integer number (3658028).

Almost surely, 2^21449217 is an apocalyptic number.

It is an amenable number.

21449217 is a deficient number, since it is larger than the sum of its proper divisors (7815007).

21449217 is a wasteful number, since it uses less digits than its factorization.

21449217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166319.

The product of its digits is 4032, while the sum is 30.

The square root of 21449217 is about 4631.3299385814. The cubic root of 21449217 is about 277.8457859734.

The spelling of 21449217 in words is "twenty-one million, four hundred forty-nine thousand, two hundred seventeen".