2261286721 has 4 divisors (see below), whose sum is σ = 2261426112. Its totient is φ = 2261147332.

The previous prime is 2261286707. The next prime is 2261286733. The reversal of 2261286721 is 1276821622.

It is a happy number.

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 a cyclic number.

It is not a de Polignac number, because 2261286721 - 2¹³ = 2261278529 is a prime.

It is a super-2 number, since 2×2261286721² = 10226835269141863682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2261286751) 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, 41581 + ... + 79066.

It is an arithmetic number, because the mean of its divisors is an integer number (565356528).

Almost surely, 2^2261286721 is an apocalyptic number.

It is an amenable number.

2261286721 is a deficient number, since it is larger than the sum of its proper divisors (139391).

2261286721 is a wasteful number, since it uses less digits than its factorization.

2261286721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139390.

The product of its digits is 32256, while the sum is 37.

The square root of 2261286721 is about 47552.9885601315. The cubic root of 2261286721 is about 1312.5581233338.

The spelling of 2261286721 in words is "two billion, two hundred sixty-one million, two hundred eighty-six thousand, seven hundred twenty-one".