21245249 has 8 divisors (see below), whose sum is σ = 22586880. Its totient is φ = 19926000.

The previous prime is 21245227. The next prime is 21245281. The reversal of 21245249 is 94254212.

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 21245249 - 2¹² = 21241153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21245219) 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, 3617 + ... + 7454.

It is an arithmetic number, because the mean of its divisors is an integer number (2823360).

Almost surely, 2^21245249 is an apocalyptic number.

It is an amenable number.

21245249 is a deficient number, since it is larger than the sum of its proper divisors (1341631).

21245249 is a wasteful number, since it uses less digits than its factorization.

21245249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11191.

The product of its digits is 5760, while the sum is 29.

The square root of 21245249 is about 4609.2568815374. The cubic root of 21245249 is about 276.9622690118.

The spelling of 21245249 in words is "twenty-one million, two hundred forty-five thousand, two hundred forty-nine".