218115515940 has 288 divisors, whose sum is σ = 722456340480. Its totient is φ = 49015701504.

The previous prime is 218115515903. The next prime is 218115515963. The reversal of 218115515940 is 49515511812.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 218115515892 and 218115515901.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 75759421 + ... + 75762299.

It is an arithmetic number, because the mean of its divisors is an integer number (2508528960).

Almost surely, 2^218115515940 is an apocalyptic number.

218115515940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218115515940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (361228170240).

218115515940 is an abundant number, since it is smaller than the sum of its proper divisors (504340824540).

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

218115515940 is a wasteful number, since it uses less digits than its factorization.

218115515940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3331 (or 3322 counting only the distinct ones).

The product of its (nonzero) digits is 72000, while the sum is 42.

The spelling of 218115515940 in words is "two hundred eighteen billion, one hundred fifteen million, five hundred fifteen thousand, nine hundred forty".