1001000001000 has 128 divisors (see below), whose sum is σ = 3306833112960. Its totient is φ = 251231360000.

The previous prime is 1001000000993. The next prime is 1001000001007. The reversal of 1001000001000 is 1000001001.

It is an interprime number because it is at equal distance from previous prime (1001000000993) and next prime (1001000001007).

It is a Harshad number since it is a multiple of its sum of digits (3).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is not an unprimeable number, because it can be changed into a prime (1001000001007) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9762726 + ... + 9864725.

It is an arithmetic number, because the mean of its divisors is an integer number (25834633695).

Almost surely, 2^{1001000001000} is an apocalyptic number.

1001000001000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001000001000 is an abundant number, since it is smaller than the sum of its proper divisors (2305833111960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1001000001000 is a wasteful number, since it uses less digits than its factorization.

1001000001000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19627492 (or 19627478 counting only the distinct ones).

The product of its (nonzero) digits is 1, while the sum is 3.

Adding to 1001000001000 its reverse (1000001001), we get a palindrome (1002000002001).

Subtracting from 1001000001000 its reverse (1000001001), we obtain a palindrome (999999999999).

The spelling of 1001000001000 in words is "one trillion, one billion, one thousand".