2091761 has 6 divisors (see below), whose sum is σ = 2433330. Its totient is φ = 1792896.

The previous prime is 2091737. The next prime is 2091763. The reversal of 2091761 is 1671902.

It can be written as a sum of positive squares in only one way, i.e., 1677025 + 414736 = 1295^2 + 644^2 .

It is not a de Polignac number, because 2091761 - 2¹⁸ = 1829617 is a prime.

It is a super-2 number, since 2×2091761² = 8750928162242, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2091761.

It is not an unprimeable number, because it can be changed into a prime (2091763) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21296 + ... + 21393.

It is an arithmetic number, because the mean of its divisors is an integer number (405555).

2^2091761 is an apocalyptic number.

It is an amenable number.

2091761 is a deficient number, since it is larger than the sum of its proper divisors (341569).

2091761 is an equidigital number, since it uses as much as digits as its factorization.

2091761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42703 (or 42696 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 2091761 is about 1446.2921558247. The cubic root of 2091761 is about 127.8902257074.

The spelling of 2091761 in words is "two million, ninety-one thousand, seven hundred sixty-one".