2218640421 has 16 divisors (see below), whose sum is σ = 3162096000. Its totient is φ = 1380276480.

The previous prime is 2218640419. The next prime is 2218640423. The reversal of 2218640421 is 1240468122.

It is an interprime number because it is at equal distance from previous prime (2218640419) and next prime (2218640423).

It is not a de Polignac number, because 2218640421 - 2¹ = 2218640419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2218640423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 389296 + ... + 394953.

It is an arithmetic number, because the mean of its divisors is an integer number (197631000).

Almost surely, 2^2218640421 is an apocalyptic number.

It is an amenable number.

2218640421 is a deficient number, since it is larger than the sum of its proper divisors (943455579).

2218640421 is a wasteful number, since it uses less digits than its factorization.

2218640421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 784316.

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 2218640421 is about 47102.4460192886. The cubic root of 2218640421 is about 1304.2543894793.

The spelling of 2218640421 in words is "two billion, two hundred eighteen million, six hundred forty thousand, four hundred twenty-one".