2142421 has 4 divisors (see below), whose sum is σ = 2255200. Its totient is φ = 2029644.

The previous prime is 2142403. The next prime is 2142431. The reversal of 2142421 is 1242412.

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 2142421 - 2⁷ = 2142293 is a prime.

It is a Duffinian number.

2142421 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 2142395 and 2142404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2142431) 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, 56361 + ... + 56398.

It is an arithmetic number, because the mean of its divisors is an integer number (563800).

2^2142421 is an apocalyptic number.

It is an amenable number.

2142421 is a deficient number, since it is larger than the sum of its proper divisors (112779).

2142421 is a wasteful number, since it uses less digits than its factorization.

2142421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112778.

The product of its digits is 128, while the sum is 16.

The square root of 2142421 is about 1463.7011306957. The cubic root of 2142421 is about 128.9144516226.

Adding to 2142421 its reverse (1242412), we get a palindrome (3384833).

Subtracting from 2142421 its reverse (1242412), we obtain a palindrome (900009).

The spelling of 2142421 in words is "two million, one hundred forty-two thousand, four hundred twenty-one".