646302331 has 2 divisors, whose sum is σ = 646302332. Its totient is φ = 646302330.

The previous prime is 646302329. The next prime is 646302337. The reversal of 646302331 is 133203646.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 646302331 - 2¹ = 646302329 is a prime.

It is a super-2 number, since 2×646302331² = 835413406112067122, which contains 22 as substring.

Together with 646302329, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 646302331.

It is not a weakly prime, because it can be changed into another prime (646302337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323151165 + 323151166.

It is an arithmetic number, because the mean of its divisors is an integer number (323151166).

Almost surely, 2^646302331 is an apocalyptic number.

646302331 is a deficient number, since it is larger than the sum of its proper divisors (1).

646302331 is an equidigital number, since it uses as much as digits as its factorization.

646302331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 28.

The square root of 646302331 is about 25422.4768856223. The cubic root of 646302331 is about 864.5933830139.

Adding to 646302331 its reverse (133203646), we get a palindrome (779505977).

The spelling of 646302331 in words is "six hundred forty-six million, three hundred two thousand, three hundred thirty-one".