218479638 has 32 divisors (see below), whose sum is σ = 477211392. Its totient is φ = 66276000.

The previous prime is 218479633. The next prime is 218479663. The reversal of 218479638 is 836974812.

It is a super-2 number, since 2×218479638² = 95466704441222088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218479633) 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, 14188 + ... + 25263.

It is an arithmetic number, because the mean of its divisors is an integer number (14912856).

Almost surely, 2^218479638 is an apocalyptic number.

218479638 is an abundant number, since it is smaller than the sum of its proper divisors (258731754).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

218479638 is a wasteful number, since it uses less digits than its factorization.

218479638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39540.

The product of its digits is 580608, while the sum is 48.

The square root of 218479638 is about 14781.0567281233. The cubic root of 218479638 is about 602.2872309893.

The spelling of 218479638 in words is "two hundred eighteen million, four hundred seventy-nine thousand, six hundred thirty-eight".