21740159 has 8 divisors (see below), whose sum is σ = 25074720. Its totient is φ = 18462816.

The previous prime is 21740141. The next prime is 21740197. The reversal of 21740159 is 95104712.

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 21740159 - 2⁸ = 21739903 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21740659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13484 + ... + 15009.

It is an arithmetic number, because the mean of its divisors is an integer number (3134340).

Almost surely, 2^21740159 is an apocalyptic number.

21740159 is a deficient number, since it is larger than the sum of its proper divisors (3334561).

21740159 is a wasteful number, since it uses less digits than its factorization.

21740159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28609.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 21740159 is about 4662.6343412281. The cubic root of 21740159 is about 279.0964025834.

The spelling of 21740159 in words is "twenty-one million, seven hundred forty thousand, one hundred fifty-nine".