7930718821 has 4 divisors (see below), whose sum is σ = 7930972192. Its totient is φ = 7930465452.

The previous prime is 7930718819. The next prime is 7930718837. The reversal of 7930718821 is 1288170397.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1288170397 = 311 ⋅4142027.

It is a cyclic number.

It is not a de Polignac number, because 7930718821 - 2¹ = 7930718819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7930718891) 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, 71811 + ... + 144976.

It is an arithmetic number, because the mean of its divisors is an integer number (1982743048).

Almost surely, 2^7930718821 is an apocalyptic number.

It is an amenable number.

7930718821 is a deficient number, since it is larger than the sum of its proper divisors (253371).

7930718821 is a wasteful number, since it uses less digits than its factorization.

7930718821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253370.

The product of its (nonzero) digits is 169344, while the sum is 46.

The square root of 7930718821 is about 89054.5833800821. The cubic root of 7930718821 is about 1994.2098215101.

The spelling of 7930718821 in words is "seven billion, nine hundred thirty million, seven hundred eighteen thousand, eight hundred twenty-one".