2011691 has 8 divisors (see below), whose sum is σ = 2208000. Its totient is φ = 1817640.

The previous prime is 2011673. The next prime is 2011697. The reversal of 2011691 is 1961102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2011691 - 2¹⁰ = 2010667 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2011697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1730 + ... + 2648.

It is an arithmetic number, because the mean of its divisors is an integer number (276000).

2^2011691 is an apocalyptic number.

2011691 is a deficient number, since it is larger than the sum of its proper divisors (196309).

2011691 is a wasteful number, since it uses less digits than its factorization.

2011691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1129.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 2011691 is about 1418.3409322162. The cubic root of 2011691 is about 126.2371238053.

Adding to 2011691 its reverse (1961102), we get a palindrome (3972793).

It can be divided in two parts, 20 and 11691, that added together give a palindrome (11711).

The spelling of 2011691 in words is "two million, eleven thousand, six hundred ninety-one".