171664749 has 6 divisors (see below), whose sum is σ = 247960206. Its totient is φ = 114443160.

The previous prime is 171664733. The next prime is 171664769. The reversal of 171664749 is 947466171.

171664749 is a `hidden beast` number, since 17 + 166 + 474 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 160655625 + 11009124 = 12675^2 + 3318^2 .

It is not a de Polignac number, because 171664749 - 2⁴ = 171664733 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171664769) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9536922 + ... + 9536939.

It is an arithmetic number, because the mean of its divisors is an integer number (41326701).

Almost surely, 2^171664749 is an apocalyptic number.

It is an amenable number.

171664749 is a deficient number, since it is larger than the sum of its proper divisors (76295457).

171664749 is a wasteful number, since it uses less digits than its factorization.

171664749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19073867 (or 19073864 counting only the distinct ones).

The product of its digits is 254016, while the sum is 45.

The square root of 171664749 is about 13102.0894898486. The cubic root of 171664749 is about 555.7682178745.

The spelling of 171664749 in words is "one hundred seventy-one million, six hundred sixty-four thousand, seven hundred forty-nine".