218809572 has 12 divisors (see below), whose sum is σ = 510555696. Its totient is φ = 72936520.

The previous prime is 218809571. The next prime is 218809573. The reversal of 218809572 is 275908812.

It is an interprime number because it is at equal distance from previous prime (218809571) and next prime (218809573).

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (218809571) 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, 9117054 + ... + 9117077.

It is an arithmetic number, because the mean of its divisors is an integer number (42546308).

Almost surely, 2^218809572 is an apocalyptic number.

It is an amenable number.

218809572 is an abundant number, since it is smaller than the sum of its proper divisors (291746124).

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

218809572 is a wasteful number, since it uses less digits than its factorization.

218809572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18234138 (or 18234136 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 42.

The square root of 218809572 is about 14792.2132218272. The cubic root of 218809572 is about 602.5902570775.

The spelling of 218809572 in words is "two hundred eighteen million, eight hundred nine thousand, five hundred seventy-two".