2271685561 has 4 divisors (see below), whose sum is σ = 2276046324. Its totient is φ = 2267324800.

The previous prime is 2271685553. The next prime is 2271685579. The reversal of 2271685561 is 1655861722.

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 1195845561 + 1075840000 = 34581^2 + 32800^2 .

It is a cyclic number.

It is not a de Polignac number, because 2271685561 - 2³ = 2271685553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2271685501) 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, 2179600 + ... + 2180641.

It is an arithmetic number, because the mean of its divisors is an integer number (569011581).

Almost surely, 2^2271685561 is an apocalyptic number.

It is an amenable number.

2271685561 is a deficient number, since it is larger than the sum of its proper divisors (4360763).

2271685561 is an equidigital number, since it uses as much as digits as its factorization.

2271685561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4360762.

The product of its digits is 201600, while the sum is 43.

The square root of 2271685561 is about 47662.2026452828. The cubic root of 2271685561 is about 1314.5670404517.

The spelling of 2271685561 in words is "two billion, two hundred seventy-one million, six hundred eighty-five thousand, five hundred sixty-one".