123636643 has 4 divisors (see below), whose sum is σ = 133147168. Its totient is φ = 114126120.

The previous prime is 123636619. The next prime is 123636673. The reversal of 123636643 is 346636321.

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 123636643 - 2⁹ = 123636131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 123636599 and 123636608.

It is not an unprimeable number, because it can be changed into a prime (123636673) 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, 4755243 + ... + 4755268.

It is an arithmetic number, because the mean of its divisors is an integer number (33286792).

Almost surely, 2^123636643 is an apocalyptic number.

123636643 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

123636643 is a deficient number, since it is larger than the sum of its proper divisors (9510525).

123636643 is an equidigital number, since it uses as much as digits as its factorization.

123636643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9510524.

The product of its digits is 46656, while the sum is 34.

The square root of 123636643 is about 11119.2015450751. The cubic root of 123636643 is about 498.1755414661.

The spelling of 123636643 in words is "one hundred twenty-three million, six hundred thirty-six thousand, six hundred forty-three".