168139872 has 72 divisors (see below), whose sum is σ = 482017536. Its totient is φ = 55593216.

The previous prime is 168139871. The next prime is 168139889. The reversal of 168139872 is 278931861.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168139871) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34278 + ... + 38874.

It is an arithmetic number, because the mean of its divisors is an integer number (6694688).

Almost surely, 2^168139872 is an apocalyptic number.

168139872 is a gapful number since it is divisible by the number (12) 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 168139872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241008768).

168139872 is an abundant number, since it is smaller than the sum of its proper divisors (313877664).

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

168139872 is a wasteful number, since it uses less digits than its factorization.

168139872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4740 (or 4729 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 168139872 is about 12966.8759537523. The cubic root of 168139872 is about 551.9379262272.

The spelling of 168139872 in words is "one hundred sixty-eight million, one hundred thirty-nine thousand, eight hundred seventy-two".