1091000001 has 16 divisors (see below), whose sum is σ = 1790359424. Its totient is φ = 575472384.

The previous prime is 1090999997. The next prime is 1091000017. The reversal of 1091000001 is 1000001901.

It is not a de Polignac number, because 1091000001 - 2² = 1090999997 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1091000021) 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, 1997896 + ... + 1998441.

It is an arithmetic number, because the mean of its divisors is an integer number (111897464).

Almost surely, 2^1091000001 is an apocalyptic number.

It is an amenable number.

1091000001 is a deficient number, since it is larger than the sum of its proper divisors (699359423).

1091000001 is a wasteful number, since it uses less digits than its factorization.

1091000001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3996360.

The product of its (nonzero) digits is 9, while the sum is 12.

The square root of 1091000001 is about 33030.2891449651. The cubic root of 1091000001 is about 1029.4570931565.

Adding to 1091000001 its reverse (1000001901), we get a palindrome (2091001902).

The spelling of 1091000001 in words is "one billion, ninety-one million, one", and thus it is an aban number and an uban number.