21313249 has 8 divisors (see below), whose sum is σ = 22288320. Its totient is φ = 20342256.

The previous prime is 21313247. The next prime is 21313283. The reversal of 21313249 is 94231312.

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 21313249 - 2¹ = 21313247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21313241) 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, 15654 + ... + 16960.

It is an arithmetic number, because the mean of its divisors is an integer number (2786040).

Almost surely, 2^21313249 is an apocalyptic number.

It is an amenable number.

21313249 is a deficient number, since it is larger than the sum of its proper divisors (975071).

21313249 is a wasteful number, since it uses less digits than its factorization.

21313249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2039.

The product of its digits is 1296, while the sum is 25.

The square root of 21313249 is about 4616.6274486902. The cubic root of 21313249 is about 277.2574467942.

The spelling of 21313249 in words is "twenty-one million, three hundred thirteen thousand, two hundred forty-nine".