6777777889 has 4 divisors (see below), whose sum is σ = 7176470724. Its totient is φ = 6379085056.

The previous prime is 6777777857. The next prime is 6777777913. The reversal of 6777777889 is 9887777776.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4075545600 + 2702232289 = 63840^2 + 51983^2 .

It is a cyclic number.

It is not a de Polignac number, because 6777777889 - 2⁵ = 6777777857 is a prime.

It is a super-2 number, since 2×6777777889² = 91876546225234592642, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (6777777689) 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, 199346392 + ... + 199346425.

It is an arithmetic number, because the mean of its divisors is an integer number (1794117681).

Almost surely, 2^6777777889 is an apocalyptic number.

It is an amenable number.

6777777889 is a deficient number, since it is larger than the sum of its proper divisors (398692835).

6777777889 is a wasteful number, since it uses less digits than its factorization.

6777777889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398692834.

The product of its digits is 406594944, while the sum is 73.

The square root of 6777777889 is about 82327.2609103449. The cubic root of 6777777889 is about 1892.4704673002.

The spelling of 6777777889 in words is "six billion, seven hundred seventy-seven million, seven hundred seventy-seven thousand, eight hundred eighty-nine".