2218421 has 8 divisors (see below), whose sum is σ = 2380320. Its totient is φ = 2061072.

The previous prime is 2218367. The next prime is 2218423. The reversal of 2218421 is 1248122.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2218421 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2218393 and 2218402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2218423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 95 + ... + 2108.

It is an arithmetic number, because the mean of its divisors is an integer number (297540).

2^2218421 is an apocalyptic number.

It is an amenable number.

2218421 is a deficient number, since it is larger than the sum of its proper divisors (161899).

2218421 is a wasteful number, since it uses less digits than its factorization.

2218421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2275.

The product of its digits is 256, while the sum is 20.

The square root of 2218421 is about 1489.4364706156. The cubic root of 2218421 is about 130.4211391639.

Subtracting from 2218421 its reverse (1248122), we obtain a cube (970299 = 99³).

The spelling of 2218421 in words is "two million, two hundred eighteen thousand, four hundred twenty-one".