172011166721280 has 720 divisors, whose sum is σ = 648258087227520. Its totient is φ = 43430193709056.

The previous prime is 172011166721263. The next prime is 172011166721369. The reversal of 172011166721280 is 82127661110271.

172011166721280 is a `hidden beast` number, since 1 + 7 + 201 + 1 + 166 + 7 + 2 + 1 + 280 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3512342874 + ... + 3512391846.

Almost surely, 2^{172011166721280} is an apocalyptic number.

172011166721280 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 172011166721280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324129043613760).

172011166721280 is an abundant number, since it is smaller than the sum of its proper divisors (476246920506240).

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

172011166721280 is a wasteful number, since it uses less digits than its factorization.

172011166721280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50808 (or 50785 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 45.

The spelling of 172011166721280 in words is "one hundred seventy-two trillion, eleven billion, one hundred sixty-six million, seven hundred twenty-one thousand, two hundred eighty".