7065075721 has 4 divisors (see below), whose sum is σ = 7707355344. Its totient is φ = 6422796100.

The previous prime is 7065075683. The next prime is 7065075733. The reversal of 7065075721 is 1275705607.

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 7065075721 - 2¹⁵ = 7065042953 is a prime.

It is a Smith number, since the sum of its digits (40) 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 not an unprimeable number, because it can be changed into a prime (7065075791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 321139795 + ... + 321139816.

It is an arithmetic number, because the mean of its divisors is an integer number (1926838836).

Almost surely, 2^7065075721 is an apocalyptic number.

It is an amenable number.

7065075721 is a deficient number, since it is larger than the sum of its proper divisors (642279623).

7065075721 is a wasteful number, since it uses less digits than its factorization.

7065075721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642279622.

The product of its (nonzero) digits is 102900, while the sum is 40.

The square root of 7065075721 is about 84054.0047885882. The cubic root of 7065075721 is about 1918.8407825481.

The spelling of 7065075721 in words is "seven billion, sixty-five million, seventy-five thousand, seven hundred twenty-one".