328681661 has 24 divisors (see below), whose sum is σ = 435253824. Its totient is φ = 244970880.

The previous prime is 328681651. The next prime is 328681729. The reversal of 328681661 is 166186823.

It is not a de Polignac number, because 328681661 - 2⁶ = 328681597 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 (328681601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 860 + ... + 25653.

It is an arithmetic number, because the mean of its divisors is an integer number (18135576).

Almost surely, 2^328681661 is an apocalyptic number.

It is an amenable number.

328681661 is a deficient number, since it is larger than the sum of its proper divisors (106572163).

328681661 is a wasteful number, since it uses less digits than its factorization.

328681661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26561 (or 26554 counting only the distinct ones).

The product of its digits is 82944, while the sum is 41.

The square root of 328681661 is about 18129.5797248585. The cubic root of 328681661 is about 690.1208644957.

The spelling of 328681661 in words is "three hundred twenty-eight million, six hundred eighty-one thousand, six hundred sixty-one".