8161645 has 16 divisors (see below), whose sum is σ = 10158768. Its totient is φ = 6289920.

The previous prime is 8161631. The next prime is 8161661. The reversal of 8161645 is 5461618.

It can be written as a sum of positive squares in 8 ways, for example, as 158404 + 8003241 = 398^2 + 2829^2 .

It is not a de Polignac number, because 8161645 - 2¹⁵ = 8128877 is a prime.

It is a super-3 number, since 3×8161645³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

Its product of digits (5760) is a multiple of the sum of its prime divisors (480).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28905 + ... + 29185.

It is an arithmetic number, because the mean of its divisors is an integer number (634923).

Almost surely, 2^8161645 is an apocalyptic number.

It is an amenable number.

8161645 is a deficient number, since it is larger than the sum of its proper divisors (1997123).

8161645 is a wasteful number, since it uses less digits than its factorization.

8161645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480.

The product of its digits is 5760, while the sum is 31.

The square root of 8161645 is about 2856.8592894996. The cubic root of 8161645 is about 201.3380695517.

The spelling of 8161645 in words is "eight million, one hundred sixty-one thousand, six hundred forty-five".