20805241 has 4 divisors (see below), whose sum is σ = 20828800. Its totient is φ = 20781684.

The previous prime is 20805223. The next prime is 20805259. The reversal of 20805241 is 14250802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (20805223) and next prime (20805259).

It is a cyclic number.

It is not a de Polignac number, because 20805241 - 2²¹ = 18708089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20805341) 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, 10401 + ... + 12238.

It is an arithmetic number, because the mean of its divisors is an integer number (5207200).

Almost surely, 2^20805241 is an apocalyptic number.

It is an amenable number.

20805241 is a deficient number, since it is larger than the sum of its proper divisors (23559).

20805241 is an equidigital number, since it uses as much as digits as its factorization.

20805241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23558.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 20805241 is about 4561.2762468414. The cubic root of 20805241 is about 275.0368699877.

The spelling of 20805241 in words is "twenty million, eight hundred five thousand, two hundred forty-one".