21835241 has 4 divisors (see below), whose sum is σ = 21900372. Its totient is φ = 21770112.

The previous prime is 21835223. The next prime is 21835267. The reversal of 21835241 is 14253812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14409616 + 7425625 = 3796^2 + 2725^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21835241 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21835241.

It is not an unprimeable number, because it can be changed into a prime (21835201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32060 + ... + 32733.

It is an arithmetic number, because the mean of its divisors is an integer number (5475093).

Almost surely, 2^21835241 is an apocalyptic number.

It is an amenable number.

21835241 is a deficient number, since it is larger than the sum of its proper divisors (65131).

21835241 is an equidigital number, since it uses as much as digits as its factorization.

21835241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65130.

The product of its digits is 1920, while the sum is 26.

The square root of 21835241 is about 4672.8193844830. The cubic root of 21835241 is about 279.5026929378.

The spelling of 21835241 in words is "twenty-one million, eight hundred thirty-five thousand, two hundred forty-one".