171681372 has 18 divisors (see below), whose sum is σ = 433972448. Its totient is φ = 57227112.

The previous prime is 171681343. The next prime is 171681383. The reversal of 171681372 is 273186171.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 4768927 = 171681372 / (1 + 7 + 1 + 6 + 8 + 1 + 3 + 7 + 2).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2384428 + ... + 2384499.

Almost surely, 2^171681372 is an apocalyptic number.

171681372 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

171681372 is an abundant number, since it is smaller than the sum of its proper divisors (262291076).

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

171681372 is a wasteful number, since it uses less digits than its factorization.

171681372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4768937 (or 4768932 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 171681372 is about 13102.7238389581. The cubic root of 171681372 is about 555.7861563990.

The spelling of 171681372 in words is "one hundred seventy-one million, six hundred eighty-one thousand, three hundred seventy-two".