201051805 has 4 divisors (see below), whose sum is σ = 241262172. Its totient is φ = 160841440.

The previous prime is 201051797. The next prime is 201051811. The reversal of 201051805 is 508150102.

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 103002201 + 98049604 = 10149^2 + 9902^2 .

It is not a de Polignac number, because 201051805 - 2³ = 201051797 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20105176 + ... + 20105185.

It is an arithmetic number, because the mean of its divisors is an integer number (60315543).

Almost surely, 2^201051805 is an apocalyptic number.

It is an amenable number.

201051805 is a deficient number, since it is larger than the sum of its proper divisors (40210367).

201051805 is an equidigital number, since it uses as much as digits as its factorization.

201051805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40210366.

The product of its (nonzero) digits is 400, while the sum is 22.

The square root of 201051805 is about 14179.2737825320. The cubic root of 201051805 is about 585.8269212436.

The spelling of 201051805 in words is "two hundred one million, fifty-one thousand, eight hundred five".