21359249 has 16 divisors (see below), whose sum is σ = 24113280. Its totient is φ = 18817920.

The previous prime is 21359243. The next prime is 21359257. The reversal of 21359249 is 94295312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21359249 is a prime.

It is a super-3 number, since 3×21359249³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21359243) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15509 + ... + 16829.

It is an arithmetic number, because the mean of its divisors is an integer number (1507080).

Almost surely, 2^21359249 is an apocalyptic number.

It is an amenable number.

21359249 is a deficient number, since it is larger than the sum of its proper divisors (2754031).

21359249 is a wasteful number, since it uses less digits than its factorization.

21359249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1400.

The product of its digits is 19440, while the sum is 35.

The square root of 21359249 is about 4621.6067552313. The cubic root of 21359249 is about 277.4567700426.

The spelling of 21359249 in words is "twenty-one million, three hundred fifty-nine thousand, two hundred forty-nine".