171972081 has 36 divisors (see below), whose sum is σ = 266309316. Its totient is φ = 106867200.

The previous prime is 171972029. The next prime is 171972083. The reversal of 171972081 is 180279171.

It can be written as a sum of positive squares in 2 ways, for example, as 17715681 + 154256400 = 4209^2 + 12420^2 .

It is not a de Polignac number, because 171972081 - 2¹⁷ = 171841009 is a prime.

It is a super-2 number, since 2×171972081² = 59148793286941122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171972083) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 194761 + ... + 195641.

It is an arithmetic number, because the mean of its divisors is an integer number (7397481).

Almost surely, 2^171972081 is an apocalyptic number.

It is an amenable number.

171972081 is a deficient number, since it is larger than the sum of its proper divisors (94337235).

171972081 is a wasteful number, since it uses less digits than its factorization.

171972081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974 (or 948 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 36.

The square root of 171972081 is about 13113.8126035108. The cubic root of 171972081 is about 556.0996847386.

The spelling of 171972081 in words is "one hundred seventy-one million, nine hundred seventy-two thousand, eighty-one".