810001005 has 64 divisors (see below), whose sum is σ = 1499904000. Its totient is φ = 369388800.

The previous prime is 810000977. The next prime is 810001007. The reversal of 810001005 is 500100018.

It is a happy number.

It is not a de Polignac number, because 810001005 - 2⁵ = 810000973 is a prime.

It is a super-2 number, since 2×810001005² = 1312203256202020050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (810001007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 229746 + ... + 233244.

It is an arithmetic number, because the mean of its divisors is an integer number (23436000).

Almost surely, 2^810001005 is an apocalyptic number.

It is an amenable number.

810001005 is a deficient number, since it is larger than the sum of its proper divisors (689902995).

810001005 is a wasteful number, since it uses less digits than its factorization.

810001005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3602.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 810001005 is about 28460.5165975602. The cubic root of 810001005 is about 932.1701373130.

The spelling of 810001005 in words is "eight hundred ten million, one thousand, five".