2113921 has 16 divisors (see below), whose sum is σ = 2383360. Its totient is φ = 1866240.

The previous prime is 2113913. The next prime is 2113931. The reversal of 2113921 is 1293112.

It is a 3-Lehmer number, since φ(2113921) divides (2113921-1)³.

It is a cyclic number.

It is a Carmichael number.

It is not a de Polignac number, because 2113921 - 2³ = 2113913 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a deceptive number, since it divides R_2113920.

It is not an unprimeable number, because it can be changed into a prime (2113901) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 21745 + ... + 21841.

It is an arithmetic number, because the mean of its divisors is an integer number (148960).

It is a Poulet number, since it divides 2^2113920-1.

2^2113921 is an apocalyptic number.

It is an amenable number.

2113921 is a deficient number, since it is larger than the sum of its proper divisors (269439).

2113921 is a wasteful number, since it uses less digits than its factorization.

2113921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184.

The product of its digits is 108, while the sum is 19.

The square root of 2113921 is about 1453.9329420575. The cubic root of 2113921 is about 128.3402608655.

The spelling of 2113921 in words is "two million, one hundred thirteen thousand, nine hundred twenty-one".