21758241 has 8 divisors (see below), whose sum is σ = 29162080. Its totient is φ = 14429952.

The previous prime is 21758221. The next prime is 21758267. The reversal of 21758241 is 14285712.

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

It is not a de Polignac number, because 21758241 - 2¹¹ = 21756193 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21758199 and 21758208.

It is not an unprimeable number, because it can be changed into a prime (21758221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18211 + ... + 19368.

It is an arithmetic number, because the mean of its divisors is an integer number (3645260).

Almost surely, 2^21758241 is an apocalyptic number.

It is an amenable number.

21758241 is a deficient number, since it is larger than the sum of its proper divisors (7403839).

21758241 is a wasteful number, since it uses less digits than its factorization.

21758241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37775.

The product of its digits is 4480, while the sum is 30.

The square root of 21758241 is about 4664.5729708088. The cubic root of 21758241 is about 279.1737590040.

The spelling of 21758241 in words is "twenty-one million, seven hundred fifty-eight thousand, two hundred forty-one".