171997980 has 192 divisors, whose sum is σ = 611573760. Its totient is φ = 35078400.

The previous prime is 171997963. The next prime is 171998011. The reversal of 171997980 is 89799171.

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, 272265 + ... + 272895.

It is an arithmetic number, because the mean of its divisors is an integer number (3185280).

Almost surely, 2^171997980 is an apocalyptic number.

171997980 is a gapful number since it is divisible by the number (10) 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 171997980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (305786880).

171997980 is an abundant number, since it is smaller than the sum of its proper divisors (439575780).

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

171997980 is a wasteful number, since it uses less digits than its factorization.

171997980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720 (or 718 counting only the distinct ones).

The product of its (nonzero) digits is 285768, while the sum is 51.

The square root of 171997980 is about 13114.8000365999. The cubic root of 171997980 is about 556.1275995464.

It can be divided in two parts, 1719 and 97980, that added together give a palindrome (99699).

The spelling of 171997980 in words is "one hundred seventy-one million, nine hundred ninety-seven thousand, nine hundred eighty".