21364249 has 8 divisors (see below), whose sum is σ = 21954240. Its totient is φ = 20778576.

The previous prime is 21364237. The next prime is 21364267. The reversal of 21364249 is 94246312.

It is a happy number.

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 21364249 - 2¹⁹ = 20839961 is a prime.

It is a super-2 number, since 2×21364249² = 912862270668002, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21364249.

It is not an unprimeable number, because it can be changed into a prime (21364229) 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, 10644 + ... + 12490.

It is an arithmetic number, because the mean of its divisors is an integer number (2744280).

Almost surely, 2^21364249 is an apocalyptic number.

It is an amenable number.

21364249 is a deficient number, since it is larger than the sum of its proper divisors (589991).

21364249 is a wasteful number, since it uses less digits than its factorization.

21364249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2159.

The product of its digits is 10368, while the sum is 31.

The square root of 21364249 is about 4622.1476609905. The cubic root of 21364249 is about 277.4784183633.

The spelling of 21364249 in words is "twenty-one million, three hundred sixty-four thousand, two hundred forty-nine".