171439920 has 120 divisors (see below), whose sum is σ = 594402432. Its totient is φ = 44236800.

The previous prime is 171439913. The next prime is 171439921. The reversal of 171439920 is 29934171.

It is a tau number, because it is divible by the number of its divisors (120).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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 (171439921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18480 + ... + 26160.

Almost surely, 2^171439920 is an apocalyptic number.

171439920 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 171439920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (297201216).

171439920 is an abundant number, since it is smaller than the sum of its proper divisors (422962512).

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

171439920 is a wasteful number, since it uses less digits than its factorization.

171439920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7731 (or 7722 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 171439920 is about 13093.5067877173. The cubic root of 171439920 is about 555.5254823425.

The spelling of 171439920 in words is "one hundred seventy-one million, four hundred thirty-nine thousand, nine hundred twenty".