217138880 has 224 divisors, whose sum is σ = 632033280. Its totient is φ = 69488640.

The previous prime is 217138871. The next prime is 217138913. The reversal of 217138880 is 88831712.

217138880 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (224).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3680291 + ... + 3680349.

Almost surely, 2^217138880 is an apocalyptic number.

217138880 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 217138880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316016640).

217138880 is an abundant number, since it is smaller than the sum of its proper divisors (414894400).

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

217138880 is a wasteful number, since it uses less digits than its factorization.

217138880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 38.

The square root of 217138880 is about 14735.6330030304. The cubic root of 217138880 is about 601.0526705795.

The spelling of 217138880 in words is "two hundred seventeen million, one hundred thirty-eight thousand, eight hundred eighty".