2101640 has 16 divisors (see below), whose sum is σ = 4728780. Its totient is φ = 840640.

The previous prime is 2101621. The next prime is 2101651. The reversal of 2101640 is 461012.

It can be written as a sum of positive squares in 2 ways, for example, as 1943236 + 158404 = 1394^2 + 398^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26231 + ... + 26310.

2^2101640 is an apocalyptic number.

2101640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2101640 is an abundant number, since it is smaller than the sum of its proper divisors (2627140).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2101640 is a wasteful number, since it uses less digits than its factorization.

2101640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52552 (or 52548 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 2101640 is about 1449.7034179445. The cubic root of 2101640 is about 128.0912435362.

Adding to 2101640 its reverse (461012), we get a palindrome (2562652).

The spelling of 2101640 in words is "two million, one hundred one thousand, six hundred forty".