170990917 has 4 divisors (see below), whose sum is σ = 171074860. Its totient is φ = 170906976.

The previous prime is 170990867. The next prime is 170990923. The reversal of 170990917 is 719099071.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 153735201 + 17255716 = 12399^2 + 4154^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-170990917 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (170990927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38838 + ... + 43015.

It is an arithmetic number, because the mean of its divisors is an integer number (42768715).

Almost surely, 2^170990917 is an apocalyptic number.

It is an amenable number.

170990917 is a deficient number, since it is larger than the sum of its proper divisors (83943).

170990917 is an equidigital number, since it uses as much as digits as its factorization.

170990917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83942.

The product of its (nonzero) digits is 35721, while the sum is 43.

The square root of 170990917 is about 13076.3495288249. The cubic root of 170990917 is about 555.0400825960.

The spelling of 170990917 in words is "one hundred seventy million, nine hundred ninety thousand, nine hundred seventeen".