2101081 has 4 divisors (see below), whose sum is σ = 2224692. Its totient is φ = 1977472.

The previous prime is 2101067. The next prime is 2101091. The reversal of 2101081 is 1801012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1245456 + 855625 = 1116^2 + 925^2 .

It is a cyclic number.

It is not a de Polignac number, because 2101081 - 2⁷ = 2100953 is a prime.

It is a super-2 number, since 2×2101081² = 8829082737122, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2101051) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61780 + ... + 61813.

It is an arithmetic number, because the mean of its divisors is an integer number (556173).

2^2101081 is an apocalyptic number.

It is an amenable number.

2101081 is a deficient number, since it is larger than the sum of its proper divisors (123611).

2101081 is a wasteful number, since it uses less digits than its factorization.

2101081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123610.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 2101081 is about 1449.5106070671. The cubic root of 2101081 is about 128.0798858419.

Adding to 2101081 its reverse (1801012), we get a palindrome (3902093).

The spelling of 2101081 in words is "two million, one hundred one thousand, eighty-one".