328126781 has 4 divisors (see below), whose sum is σ = 328316352. Its totient is φ = 327937212.

The previous prime is 328126769. The next prime is 328126783. The reversal of 328126781 is 187621823.

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: 187621823 = 1373 ⋅136651.

It is a cyclic number.

It is not a de Polignac number, because 328126781 - 2¹⁰ = 328125757 is a prime.

It is a super-2 number, since 2×328126781² = 215334368818843922, 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 (328126783) 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, 92165 + ... + 95658.

It is an arithmetic number, because the mean of its divisors is an integer number (82079088).

Almost surely, 2^328126781 is an apocalyptic number.

It is an amenable number.

328126781 is a deficient number, since it is larger than the sum of its proper divisors (189571).

328126781 is a wasteful number, since it uses less digits than its factorization.

328126781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189570.

The product of its digits is 32256, while the sum is 38.

The square root of 328126781 is about 18114.2700929405. The cubic root of 328126781 is about 689.7322920026.

It can be divided in two parts, 32812 and 6781, that added together give a palindrome (39593).

The spelling of 328126781 in words is "three hundred twenty-eight million, one hundred twenty-six thousand, seven hundred eighty-one".