8000400005 has 54 divisors (see below), whose sum is σ = 11104624098. Its totient is φ = 5529738240.

The previous prime is 8000399993. The next prime is 8000400007. The reversal of 8000400005 is 5000040008.

It can be written as a sum of positive squares in 27 ways, for example, as 6463838404 + 1536561601 = 80398^2 + 39199^2 .

It is not a de Polignac number, because 8000400005 - 2²⁰ = 7999351429 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8000400007) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 44201015 + ... + 44201195.

It is an arithmetic number, because the mean of its divisors is an integer number (205641187).

Almost surely, 2^8000400005 is an apocalyptic number.

8000400005 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

8000400005 is a deficient number, since it is larger than the sum of its proper divisors (3104224093).

8000400005 is a wasteful number, since it uses less digits than its factorization.

8000400005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 8000400005 is about 89444.9551679691. The cubic root of 8000400005 is about 2000.0333331944.

The spelling of 8000400005 in words is "eight billion, four hundred thousand, five".