328047581 has 4 divisors (see below), whose sum is σ = 334237212. Its totient is φ = 321857952.

The previous prime is 328047557. The next prime is 328047631. The reversal of 328047581 is 185740823.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 185740823 = 13331 ⋅13933.

It can be written as a sum of positive squares in 2 ways, for example, as 292752100 + 35295481 = 17110^2 + 5941^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-328047581 is a prime.

It is a super-2 number, since 2×328047581² = 215230430799903122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (328047541) 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, 3094736 + ... + 3094841.

It is an arithmetic number, because the mean of its divisors is an integer number (83559303).

Almost surely, 2^328047581 is an apocalyptic number.

It is an amenable number.

328047581 is a deficient number, since it is larger than the sum of its proper divisors (6189631).

328047581 is an equidigital number, since it uses as much as digits as its factorization.

328047581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6189630.

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 328047581 is about 18112.0838392494. The cubic root of 328047581 is about 689.6767939488.

The spelling of 328047581 in words is "three hundred twenty-eight million, forty-seven thousand, five hundred eighty-one".