6815147977 has 6 divisors (see below), whose sum is σ = 7491030554. Its totient is φ = 6195588960.

The previous prime is 6815147971. The next prime is 6815148023. The reversal of 6815147977 is 7797415186.

It can be written as a sum of positive squares in only one way, i.e., 4420122256 + 2395025721 = 66484^2 + 48939^2 .

It is a de Polignac number, because none of the positive numbers 2^k-6815147977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6815147971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 28161648 + ... + 28161889.

Almost surely, 2^6815147977 is an apocalyptic number.

It is an amenable number.

6815147977 is a deficient number, since it is larger than the sum of its proper divisors (675882577).

6815147977 is a wasteful number, since it uses less digits than its factorization.

6815147977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56323559 (or 56323548 counting only the distinct ones).

The product of its digits is 2963520, while the sum is 55.

The square root of 6815147977 is about 82553.9095197799. The cubic root of 6815147977 is about 1895.9422151238.

The spelling of 6815147977 in words is "six billion, eight hundred fifteen million, one hundred forty-seven thousand, nine hundred seventy-seven".