20718249 has 8 divisors (see below), whose sum is σ = 27702720. Its totient is φ = 13772976.

The previous prime is 20718241. The next prime is 20718259. The reversal of 20718249 is 94281702.

It is a happy number.

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

It is not a de Polignac number, because 20718249 - 2³ = 20718241 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20718241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8542 + ... + 10695.

It is an arithmetic number, because the mean of its divisors is an integer number (3462840).

Almost surely, 2^20718249 is an apocalyptic number.

It is an amenable number.

20718249 is a deficient number, since it is larger than the sum of its proper divisors (6984471).

20718249 is a wasteful number, since it uses less digits than its factorization.

20718249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19599.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 20718249 is about 4551.7303303249. The cubic root of 20718249 is about 274.6530014554.

The spelling of 20718249 in words is "twenty million, seven hundred eighteen thousand, two hundred forty-nine".