331663643 has 2 divisors, whose sum is σ = 331663644. Its totient is φ = 331663642.

The previous prime is 331663627. The next prime is 331663681. The reversal of 331663643 is 346366133.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 331663643 - 2⁴ = 331663627 is a prime.

It is a super-2 number, since 2×331663643² = 220001544176062898, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (331663043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165831821 + 165831822.

It is an arithmetic number, because the mean of its divisors is an integer number (165831822).

Almost surely, 2^331663643 is an apocalyptic number.

331663643 is a deficient number, since it is larger than the sum of its proper divisors (1).

331663643 is an equidigital number, since it uses as much as digits as its factorization.

331663643 is an evil number, because the sum of its binary digits is even.

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

The square root of 331663643 is about 18211.6348250233. The cubic root of 331663643 is about 692.2016373379.

The spelling of 331663643 in words is "three hundred thirty-one million, six hundred sixty-three thousand, six hundred forty-three".