218640471468 has 24 divisors (see below), whose sum is σ = 540170577072. Its totient is φ = 68593089024.

The previous prime is 218640471421. The next prime is 218640471583. The reversal of 218640471468 is 864174046812.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 218640471468.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 535883305 + ... + 535883712.

It is an arithmetic number, because the mean of its divisors is an integer number (22507107378).

Almost surely, 2^218640471468 is an apocalyptic number.

It is an amenable number.

218640471468 is an abundant number, since it is smaller than the sum of its proper divisors (321530105604).

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

218640471468 is a wasteful number, since it uses less digits than its factorization.

218640471468 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1071767041 (or 1071767039 counting only the distinct ones).

The product of its (nonzero) digits is 2064384, while the sum is 51.

The spelling of 218640471468 in words is "two hundred eighteen billion, six hundred forty million, four hundred seventy-one thousand, four hundred sixty-eight".