172078640 has 80 divisors (see below), whose sum is σ = 427847616. Its totient is φ = 64204800.

The previous prime is 172078639. The next prime is 172078657. The reversal of 172078640 is 46870271.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×172078640² = 59222116688499200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 172078640.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74300 + ... + 76580.

Almost surely, 2^172078640 is an apocalyptic number.

172078640 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 172078640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (213923808).

172078640 is an abundant number, since it is smaller than the sum of its proper divisors (255768976).

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

172078640 is a wasteful number, since it uses less digits than its factorization.

172078640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2358 (or 2352 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 35.

The square root of 172078640 is about 13117.8748278828. The cubic root of 172078640 is about 556.2145196407.

The spelling of 172078640 in words is "one hundred seventy-two million, seventy-eight thousand, six hundred forty".