7868775921 has 4 divisors (see below), whose sum is σ = 10491701232. Its totient is φ = 5245850612.

The previous prime is 7868775899. The next prime is 7868775989. The reversal of 7868775921 is 1295778687.

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 7868775921 - 2¹⁵ = 7868743153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7868775991) 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, 1311462651 + ... + 1311462656.

It is an arithmetic number, because the mean of its divisors is an integer number (2622925308).

Almost surely, 2^7868775921 is an apocalyptic number.

It is an amenable number.

7868775921 is a deficient number, since it is larger than the sum of its proper divisors (2622925311).

7868775921 is a wasteful number, since it uses less digits than its factorization.

7868775921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2622925310.

The product of its digits is 11854080, while the sum is 60.

The square root of 7868775921 is about 88706.1211022103. The cubic root of 7868775921 is about 1989.0043183621.

The spelling of 7868775921 in words is "seven billion, eight hundred sixty-eight million, seven hundred seventy-five thousand, nine hundred twenty-one".