172991280 has 480 divisors, whose sum is σ = 721953792. Its totient is φ = 33454080.

The previous prime is 172991267. The next prime is 172991309. The reversal of 172991280 is 82199271.

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 95 ways as a sum of consecutive naturals, for example, 4675422 + ... + 4675458.

Almost surely, 2^172991280 is an apocalyptic number.

172991280 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 172991280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360976896).

172991280 is an abundant number, since it is smaller than the sum of its proper divisors (548962512).

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

172991280 is a wasteful number, since it uses less digits than its factorization.

172991280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 39.

The square root of 172991280 is about 13152.6149491270. The cubic root of 172991280 is about 557.1961034863.

The spelling of 172991280 in words is "one hundred seventy-two million, nine hundred ninety-one thousand, two hundred eighty".