218678678520 has 256 divisors, whose sum is σ = 690204672000. Its totient is φ = 55353715200.

The previous prime is 218678678507. The next prime is 218678678539. The reversal of 218678678520 is 25876876812.

It is a hoax number, since the sum of its digits (60) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 138491091 + ... + 138492669.

It is an arithmetic number, because the mean of its divisors is an integer number (2696112000).

Almost surely, 2^218678678520 is an apocalyptic number.

218678678520 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 218678678520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (345102336000).

218678678520 is an abundant number, since it is smaller than the sum of its proper divisors (471525993480).

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

218678678520 is a wasteful number, since it uses less digits than its factorization.

218678678520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2314 (or 2310 counting only the distinct ones).

The product of its (nonzero) digits is 18063360, while the sum is 60.

The spelling of 218678678520 in words is "two hundred eighteen billion, six hundred seventy-eight million, six hundred seventy-eight thousand, five hundred twenty".