2121421 has 4 divisors (see below), whose sum is σ = 2153152. Its totient is φ = 2089692.

The previous prime is 2121403. The next prime is 2121433. The reversal of 2121421 is 1241212.

It is a happy number.

2121421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 2121421 - 2⁵ = 2121389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15765 + ... + 15898.

It is an arithmetic number, because the mean of its divisors is an integer number (538288).

2^2121421 is an apocalyptic number.

It is an amenable number.

2121421 is a deficient number, since it is larger than the sum of its proper divisors (31731).

2121421 is an equidigital number, since it uses as much as digits as its factorization.

2121421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31730.

The product of its digits is 32, while the sum is 13.

The square root of 2121421 is about 1456.5098695169. The cubic root of 2121421 is about 128.4918615870.

Adding to 2121421 its reverse (1241212), we get a palindrome (3362633).

The spelling of 2121421 in words is "two million, one hundred twenty-one thousand, four hundred twenty-one".