216171880 has 16 divisors (see below), whose sum is σ = 486386820. Its totient is φ = 86468736.

The previous prime is 216171869. The next prime is 216171913. The reversal of 216171880 is 88171612.

It can be written as a sum of positive squares in 2 ways, for example, as 176305284 + 39866596 = 13278^2 + 6314^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2702109 + ... + 2702188.

Almost surely, 2^216171880 is an apocalyptic number.

216171880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216171880 is an abundant number, since it is smaller than the sum of its proper divisors (270214940).

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

216171880 is a wasteful number, since it uses less digits than its factorization.

216171880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5404308 (or 5404304 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 34.

The square root of 216171880 is about 14702.7847702400. The cubic root of 216171880 is about 600.1591059532.

The spelling of 216171880 in words is "two hundred sixteen million, one hundred seventy-one thousand, eight hundred eighty".