217172080 has 80 divisors (see below), whose sum is σ = 524903904. Its totient is φ = 83496960.

The previous prime is 217172069. The next prime is 217172099. The reversal of 217172080 is 80271712.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 238987 + ... + 239893.

Almost surely, 2^217172080 is an apocalyptic number.

217172080 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 217172080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (262451952).

217172080 is an abundant number, since it is smaller than the sum of its proper divisors (307731824).

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

217172080 is a wasteful number, since it uses less digits than its factorization.

217172080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1034 (or 1028 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 217172080 is about 14736.7594809714. The cubic root of 217172080 is about 601.0833021761.

The spelling of 217172080 in words is "two hundred seventeen million, one hundred seventy-two thousand, eighty".