171945640 has 32 divisors (see below), whose sum is σ = 400221000. Its totient is φ = 66406144.

The previous prime is 171945637. The next prime is 171945643. The reversal of 171945640 is 46549171.

It is an interprime number because it is at equal distance from previous prime (171945637) and next prime (171945643).

It can be written as a sum of positive squares in 4 ways, for example, as 171243396 + 702244 = 13086^2 + 838^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 171945640.

It is not an unprimeable number, because it can be changed into a prime (171945643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72955 + ... + 75274.

Almost surely, 2^171945640 is an apocalyptic number.

171945640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

171945640 is an abundant number, since it is smaller than the sum of its proper divisors (228275360).

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

171945640 is a wasteful number, since it uses less digits than its factorization.

171945640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148269 (or 148265 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 171945640 is about 13112.8044292592. The cubic root of 171945640 is about 556.0711828536.

The spelling of 171945640 in words is "one hundred seventy-one million, nine hundred forty-five thousand, six hundred forty".