6677778881 has 2 divisors, whose sum is σ = 6677778882. Its totient is φ = 6677778880.

The previous prime is 6677778839. The next prime is 6677778889. The reversal of 6677778881 is 1888777766.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6275174656 + 402604225 = 79216^2 + 20065^2 .

It is a cyclic number.

It is not a de Polignac number, because 6677778881 - 2¹⁸ = 6677516737 is a prime.

It is a super-2 number, since 2×6677778881² = 89185461567059224322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6677778889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3338889440 + 3338889441.

It is an arithmetic number, because the mean of its divisors is an integer number (3338889441).

Almost surely, 2^6677778881 is an apocalyptic number.

It is an amenable number.

6677778881 is a deficient number, since it is larger than the sum of its proper divisors (1).

6677778881 is an equidigital number, since it uses as much as digits as its factorization.

6677778881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 44255232, while the sum is 65.

The square root of 6677778881 is about 81717.6778977474. The cubic root of 6677778881 is about 1883.1171767025.

The spelling of 6677778881 in words is "six billion, six hundred seventy-seven million, seven hundred seventy-eight thousand, eight hundred eighty-one".