331643663 has 4 divisors (see below), whose sum is σ = 357154728. Its totient is φ = 306132600.

The previous prime is 331643639. The next prime is 331643671. The reversal of 331643663 is 366346133.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 331643663 - 2⁸ = 331643407 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 (331643603) 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, 12755513 + ... + 12755538.

It is an arithmetic number, because the mean of its divisors is an integer number (89288682).

Almost surely, 2^331643663 is an apocalyptic number.

331643663 is a deficient number, since it is larger than the sum of its proper divisors (25511065).

331643663 is a wasteful number, since it uses less digits than its factorization.

331643663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25511064.

The product of its digits is 69984, while the sum is 35.

The square root of 331643663 is about 18211.0862663379. The cubic root of 331643663 is about 692.1877372449.

Adding to 331643663 its reverse (366346133), we get a palindrome (697989796).

The spelling of 331643663 in words is "three hundred thirty-one million, six hundred forty-three thousand, six hundred sixty-three".