171961920 has 224 divisors, whose sum is σ = 653735040. Its totient is φ = 42301440.

The previous prime is 171961901. The next prime is 171961921. The reversal of 171961920 is 29169171.

171961920 is a `hidden beast` number, since 1 + 7 + 19 + 619 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (171961921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 111555 + ... + 113085.

It is an arithmetic number, because the mean of its divisors is an integer number (2918460).

Almost surely, 2^171961920 is an apocalyptic number.

171961920 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 171961920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326867520).

171961920 is an abundant number, since it is smaller than the sum of its proper divisors (481773120).

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

171961920 is a wasteful number, since it uses less digits than its factorization.

171961920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1570 (or 1554 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 36.

The square root of 171961920 is about 13113.4251818509. The cubic root of 171961920 is about 556.0887321077.

The spelling of 171961920 in words is "one hundred seventy-one million, nine hundred sixty-one thousand, nine hundred twenty".