2765475721 has 4 divisors (see below), whose sum is σ = 2765952000. Its totient is φ = 2764999444.

The previous prime is 2765475709. The next prime is 2765475749. The reversal of 2765475721 is 1275745672.

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 2765475721 - 2⁵ = 2765475689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2765475421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 229321 + ... + 241078.

It is an arithmetic number, because the mean of its divisors is an integer number (691488000).

Almost surely, 2^2765475721 is an apocalyptic number.

It is an amenable number.

2765475721 is a deficient number, since it is larger than the sum of its proper divisors (476279).

2765475721 is an equidigital number, since it uses as much as digits as its factorization.

2765475721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476278.

The product of its digits is 823200, while the sum is 46.

The square root of 2765475721 is about 52587.7906077067. The cubic root of 2765475721 is about 1403.6428464746.

The spelling of 2765475721 in words is "two billion, seven hundred sixty-five million, four hundred seventy-five thousand, seven hundred twenty-one".