328915091 has 4 divisors (see below), whose sum is σ = 329696784. Its totient is φ = 328133400.

The previous prime is 328915087. The next prime is 328915109. The reversal of 328915091 is 190519823.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190519823 = 13 ⋅14655371.

It is a cyclic number.

It is not a de Polignac number, because 328915091 - 2² = 328915087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (328915051) 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, 390215 + ... + 391056.

It is an arithmetic number, because the mean of its divisors is an integer number (82424196).

Almost surely, 2^328915091 is an apocalyptic number.

328915091 is a deficient number, since it is larger than the sum of its proper divisors (781693).

328915091 is an equidigital number, since it uses as much as digits as its factorization.

328915091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781692.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 328915091 is about 18136.0164038303. The cubic root of 328915091 is about 690.2842006463.

The spelling of 328915091 in words is "three hundred twenty-eight million, nine hundred fifteen thousand, ninety-one".