328331261 has 4 divisors (see below), whose sum is σ = 338922624. Its totient is φ = 317739900.

The previous prime is 328331249. The next prime is 328331291. The reversal of 328331261 is 162133823.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 162133823 = 3637 ⋅44579.

It is a cyclic number.

It is not a de Polignac number, because 328331261 - 2⁶ = 328331197 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 (328331231) 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, 5295635 + ... + 5295696.

It is an arithmetic number, because the mean of its divisors is an integer number (84730656).

Almost surely, 2^328331261 is an apocalyptic number.

328331261 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

328331261 is a deficient number, since it is larger than the sum of its proper divisors (10591363).

328331261 is a wasteful number, since it uses less digits than its factorization.

328331261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10591362.

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

The square root of 328331261 is about 18119.9133827952. The cubic root of 328331261 is about 689.8755366066.

The spelling of 328331261 in words is "three hundred twenty-eight million, three hundred thirty-one thousand, two hundred sixty-one".