2101987 has 4 divisors (see below), whose sum is σ = 2107296. Its totient is φ = 2096680.

The previous prime is 2101961. The next prime is 2102021. The reversal of 2101987 is 7891012.

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

It is a cyclic number.

It is not a de Polignac number, because 2101987 - 2¹¹ = 2099939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2101907) 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, 2008 + ... + 2869.

It is an arithmetic number, because the mean of its divisors is an integer number (526824).

2^2101987 is an apocalyptic number.

2101987 is a deficient number, since it is larger than the sum of its proper divisors (5309).

2101987 is an equidigital number, since it uses as much as digits as its factorization.

2101987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5308.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 2101987 is about 1449.8230926565. The cubic root of 2101987 is about 128.0982928272.

Adding to 2101987 its reverse (7891012), we get a palindrome (9992999).

It can be divided in two parts, 210 and 1987, that added together give a cube (2197 = 13³).

The spelling of 2101987 in words is "two million, one hundred one thousand, nine hundred eighty-seven".