326640161 has 4 divisors (see below), whose sum is σ = 329874324. Its totient is φ = 323406000.

The previous prime is 326640151. The next prime is 326640163. The reversal of 326640161 is 161046623.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 161046623 = 397 ⋅405659.

It can be written as a sum of positive squares in 2 ways, for example, as 317374225 + 9265936 = 17815^2 + 3044^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-326640161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (326640163) 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 3 ways as a sum of consecutive naturals, for example, 1616930 + ... + 1617131.

It is an arithmetic number, because the mean of its divisors is an integer number (82468581).

Almost surely, 2^326640161 is an apocalyptic number.

It is an amenable number.

326640161 is a deficient number, since it is larger than the sum of its proper divisors (3234163).

326640161 is a wasteful number, since it uses less digits than its factorization.

326640161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3234162.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 326640161 is about 18073.1890102439. The cubic root of 326640161 is about 688.6890750597.

Adding to 326640161 its reverse (161046623), we get a palindrome (487686784).

The spelling of 326640161 in words is "three hundred twenty-six million, six hundred forty thousand, one hundred sixty-one".