331327561 has 4 divisors (see below), whose sum is σ = 331403652. Its totient is φ = 331251472.

The previous prime is 331327553. The next prime is 331327573. The reversal of 331327561 is 165723133.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165723133 = 6361 ⋅26053.

It can be written as a sum of positive squares in 2 ways, for example, as 186486336 + 144841225 = 13656^2 + 12035^2 .

It is a cyclic number.

It is not a de Polignac number, because 331327561 - 2³ = 331327553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (331327531) 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, 31090 + ... + 40363.

It is an arithmetic number, because the mean of its divisors is an integer number (82850913).

Almost surely, 2^331327561 is an apocalyptic number.

It is an amenable number.

331327561 is a deficient number, since it is larger than the sum of its proper divisors (76091).

331327561 is an equidigital number, since it uses as much as digits as its factorization.

331327561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76090.

The product of its digits is 11340, while the sum is 31.

The square root of 331327561 is about 18202.4053630283. The cubic root of 331327561 is about 691.9677506494.

The spelling of 331327561 in words is "three hundred thirty-one million, three hundred twenty-seven thousand, five hundred sixty-one".