7638888889 has 4 divisors (see below), whose sum is σ = 7752902224. Its totient is φ = 7524875556.

The previous prime is 7638888857. The next prime is 7638888893. The reversal of 7638888889 is 9888888367.

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: 9888888367 = 78877 ⋅125371.

It is a cyclic number.

It is not a de Polignac number, because 7638888889 - 2⁵ = 7638888857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7638880889) 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, 57006567 + ... + 57006700.

It is an arithmetic number, because the mean of its divisors is an integer number (1938225556).

Almost surely, 2^7638888889 is an apocalyptic number.

It is an amenable number.

7638888889 is a deficient number, since it is larger than the sum of its proper divisors (114013335).

7638888889 is a wasteful number, since it uses less digits than its factorization.

7638888889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114013334.

The product of its digits is 297271296, while the sum is 73.

The square root of 7638888889 is about 87400.7373481483. The cubic root of 7638888889 is about 1969.4429174554.

The spelling of 7638888889 in words is "seven billion, six hundred thirty-eight million, eight hundred eighty-eight thousand, eight hundred eighty-nine".