2101638 has 32 divisors (see below), whose sum is σ = 5241600. Its totient is φ = 545760.

The previous prime is 2101621. The next prime is 2101651. The reversal of 2101638 is 8361012.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1813 + ... + 2736.

It is an arithmetic number, because the mean of its divisors is an integer number (163800).

2^2101638 is an apocalyptic number.

2101638 is an abundant number, since it is smaller than the sum of its proper divisors (3139962).

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

2101638 is a wasteful number, since it uses less digits than its factorization.

2101638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4572.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 2101638 is about 1449.7027281481. The cubic root of 2101638 is about 128.0912029041.

The spelling of 2101638 in words is "two million, one hundred one thousand, six hundred thirty-eight".