123543640247 has 4 divisors (see below), whose sum is σ = 123551422776. Its totient is φ = 123535857720.

The previous prime is 123543640223. The next prime is 123543640249. The reversal of 123543640247 is 742046345321.

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 123543640247 - 2³² = 119248672951 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123543640249) 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, 3867404 + ... + 3899217.

It is an arithmetic number, because the mean of its divisors is an integer number (30887855694).

Almost surely, 2^123543640247 is an apocalyptic number.

123543640247 is a deficient number, since it is larger than the sum of its proper divisors (7782529).

123543640247 is an equidigital number, since it uses as much as digits as its factorization.

123543640247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7782528.

The product of its (nonzero) digits is 483840, while the sum is 41.

Adding to 123543640247 its reverse (742046345321), we get a palindrome (865589985568).

The spelling of 123543640247 in words is "one hundred twenty-three billion, five hundred forty-three million, six hundred forty thousand, two hundred forty-seven".