331620643 has 2 divisors, whose sum is σ = 331620644. Its totient is φ = 331620642.

The previous prime is 331620617. The next prime is 331620659. The reversal of 331620643 is 346026133.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 331620643 - 2¹³ = 331612451 is a prime.

It is not a weakly prime, because it can be changed into another prime (331620043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165810321 + 165810322.

It is an arithmetic number, because the mean of its divisors is an integer number (165810322).

Almost surely, 2^331620643 is an apocalyptic number.

331620643 is a deficient number, since it is larger than the sum of its proper divisors (1).

331620643 is an equidigital number, since it uses as much as digits as its factorization.

331620643 is an odious number, because the sum of its binary digits is odd.

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

The square root of 331620643 is about 18210.4542227809. The cubic root of 331620643 is about 692.1717215307.

Adding to 331620643 its reverse (346026133), we get a palindrome (677646776).

The spelling of 331620643 in words is "three hundred thirty-one million, six hundred twenty thousand, six hundred forty-three".