12439721623 has 4 divisors (see below), whose sum is σ = 14216824720. Its totient is φ = 10662618528.

The previous prime is 12439721599. The next prime is 12439721647. The reversal of 12439721623 is 32612793421.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (12439721599) and next prime (12439721647).

It is a cyclic number.

It is not a de Polignac number, because 12439721623 - 2¹³ = 12439713431 is a prime.

It is the 111534-th Hogben number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12439701623) by changing a digit.

It is a nontrivial repunit in base 111533.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 888551538 + ... + 888551551.

It is an arithmetic number, because the mean of its divisors is an integer number (3554206180).

Almost surely, 2^12439721623 is an apocalyptic number.

12439721623 is a deficient number, since it is larger than the sum of its proper divisors (1777103097).

12439721623 is an equidigital number, since it uses as much as digits as its factorization.

12439721623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1777103096.

The product of its digits is 108864, while the sum is 40.

The spelling of 12439721623 in words is "twelve billion, four hundred thirty-nine million, seven hundred twenty-one thousand, six hundred twenty-three".