218181954479964 has 24 divisors (see below), whose sum is σ = 509093069011968. Its totient is φ = 72727055032560.

The previous prime is 218181954479963. The next prime is 218181954480029. The reversal of 218181954479964 is 469974459181812.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 218181954479964.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218181954479963) 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, 29421342 + ... + 36082949.

It is an arithmetic number, because the mean of its divisors is an integer number (21212211208832).

Almost surely, 2^{218181954479964} is an apocalyptic number.

It is an amenable number.

218181954479964 is an abundant number, since it is smaller than the sum of its proper divisors (290911114532004).

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

218181954479964 is a wasteful number, since it uses less digits than its factorization.

218181954479964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65781865 (or 65781863 counting only the distinct ones).

The product of its digits is 1254113280, while the sum is 78.

The spelling of 218181954479964 in words is "two hundred eighteen trillion, one hundred eighty-one billion, nine hundred fifty-four million, four hundred seventy-nine thousand, nine hundred sixty-four".