2566075721 has 4 divisors (see below), whose sum is σ = 2799355344. Its totient is φ = 2332796100.

The previous prime is 2566075717. The next prime is 2566075739. The reversal of 2566075721 is 1275706652.

2566075721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2566075721 - 2² = 2566075717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2566075621) 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, 116639795 + ... + 116639816.

It is an arithmetic number, because the mean of its divisors is an integer number (699838836).

Almost surely, 2^2566075721 is an apocalyptic number.

It is an amenable number.

2566075721 is a deficient number, since it is larger than the sum of its proper divisors (233279623).

2566075721 is a wasteful number, since it uses less digits than its factorization.

2566075721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233279622.

The product of its (nonzero) digits is 176400, while the sum is 41.

The square root of 2566075721 is about 50656.4479706187. The cubic root of 2566075721 is about 1369.0621248919.

The spelling of 2566075721 in words is "two billion, five hundred sixty-six million, seventy-five thousand, seven hundred twenty-one".