1001000990991 has 16 divisors (see below), whose sum is σ = 1392794726400. Its totient is φ = 638274695520.

The previous prime is 1001000990963. The next prime is 1001000991031. The reversal of 1001000990991 is 1990990001001.

1001000990991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1001000990991 - 2²³ = 1000992602383 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001000997991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 496210 + ... + 1499408.

It is an arithmetic number, because the mean of its divisors is an integer number (87049670400).

Almost surely, 2^{1001000990991} is an apocalyptic number.

1001000990991 is a deficient number, since it is larger than the sum of its proper divisors (391793735409).

1001000990991 is a wasteful number, since it uses less digits than its factorization.

1001000990991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1017686.

The product of its (nonzero) digits is 6561, while the sum is 39.

Adding to 1001000990991 its reverse (1990990001001), we get a palindrome (2991990991992).

It can be divided in two parts, 1001000 and 990991, that added together give a palindrome (1991991).

The spelling of 1001000990991 in words is "one trillion, one billion, nine hundred ninety thousand, nine hundred ninety-one".