123664643 has 2 divisors, whose sum is σ = 123664644. Its totient is φ = 123664642.

The previous prime is 123664637. The next prime is 123664691. The reversal of 123664643 is 346466321.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123664643 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (123664043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61832321 + 61832322.

It is an arithmetic number, because the mean of its divisors is an integer number (61832322).

Almost surely, 2^123664643 is an apocalyptic number.

123664643 is a deficient number, since it is larger than the sum of its proper divisors (1).

123664643 is an equidigital number, since it uses as much as digits as its factorization.

123664643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 35.

The square root of 123664643 is about 11120.4605570093. The cubic root of 123664643 is about 498.2131459118.

The spelling of 123664643 in words is "one hundred twenty-three million, six hundred sixty-four thousand, six hundred forty-three".