2116421 has 4 divisors (see below), whose sum is σ = 2119392. Its totient is φ = 2113452.

The previous prime is 2116409. The next prime is 2116423. The reversal of 2116421 is 1246112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2116421 - 2⁶ = 2116357 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2116421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2116423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 296 + ... + 2078.

It is an arithmetic number, because the mean of its divisors is an integer number (529848).

2^2116421 is an apocalyptic number.

It is an amenable number.

2116421 is a deficient number, since it is larger than the sum of its proper divisors (2971).

2116421 is a wasteful number, since it uses less digits than its factorization.

2116421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2970.

The product of its digits is 96, while the sum is 17.

The square root of 2116421 is about 1454.7924250559. The cubic root of 2116421 is about 128.3908342237.

It can be divided in two parts, 21164 and 21, that multiplied together give a palindrome (444444).

The spelling of 2116421 in words is "two million, one hundred sixteen thousand, four hundred twenty-one".