217878487200 has 1728 divisors, whose sum is σ = 966988108800. Its totient is φ = 46813593600.

The previous prime is 217878487199. The next prime is 217878487223. The reversal of 217878487200 is 2784878712.

217878487200 is a `hidden beast` number, since 2 + 1 + 78 + 78 + 487 + 20 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1304661517 + ... + 1304661683.

It is an arithmetic number, because the mean of its divisors is an integer number (559599600).

Almost surely, 2^217878487200 is an apocalyptic number.

217878487200 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 217878487200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (483494054400).

217878487200 is an abundant number, since it is smaller than the sum of its proper divisors (749109621600).

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

217878487200 is a wasteful number, since it uses less digits than its factorization.

217878487200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 2809856, while the sum is 54.

It can be divided in two parts, 217878 and 487200, that added together give a triangular number (705078 = T₁₁₈₇).

The spelling of 217878487200 in words is "two hundred seventeen billion, eight hundred seventy-eight million, four hundred eighty-seven thousand, two hundred".