2100842 has 4 divisors (see below), whose sum is σ = 3151266. Its totient is φ = 1050420.

The previous prime is 2100841. The next prime is 2100859. The reversal of 2100842 is 2480012.

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

It can be written as a sum of positive squares in only one way, i.e., 1957201 + 143641 = 1399^2 + 379^2 .

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 2100842.

It is not an unprimeable number, because it can be changed into a prime (2100841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 525209 + ... + 525212.

2^2100842 is an apocalyptic number.

2100842 is a deficient number, since it is larger than the sum of its proper divisors (1050424).

2100842 is a wasteful number, since it uses less digits than its factorization.

2100842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1050423.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2100842 is about 1449.4281631043. The cubic root of 2100842 is about 128.0750292540.

Adding to 2100842 its reverse (2480012), we get a palindrome (4580854).

The spelling of 2100842 in words is "two million, one hundred thousand, eight hundred forty-two".