2111621 has 4 divisors (see below), whose sum is σ = 2235852. Its totient is φ = 1987392.

The previous prime is 2111597. The next prime is 2111633. The reversal of 2111621 is 1261112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1188100 + 923521 = 1090^2 + 961^2 .

It is a cyclic number.

It is not a de Polignac number, because 2111621 - 2¹⁴ = 2095237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2111596 and 2111605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2111321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62090 + ... + 62123.

It is an arithmetic number, because the mean of its divisors is an integer number (558963).

2^2111621 is an apocalyptic number.

It is an amenable number.

2111621 is a deficient number, since it is larger than the sum of its proper divisors (124231).

2111621 is a wasteful number, since it uses less digits than its factorization.

2111621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124230.

The product of its digits is 24, while the sum is 14.

The square root of 2111621 is about 1453.1417687205. The cubic root of 2111621 is about 128.2936981478.

Adding to 2111621 its reverse (1261112), we get a palindrome (3372733).

The spelling of 2111621 in words is "two million, one hundred eleven thousand, six hundred twenty-one".