20123136443 has 4 divisors (see below), whose sum is σ = 20258191200. Its totient is φ = 19988081688.

The previous prime is 20123136437. The next prime is 20123136457. The reversal of 20123136443 is 34463132102.

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 20123136443 - 2¹⁰ = 20123135419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20123136343) 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, 67527155 + ... + 67527452.

It is an arithmetic number, because the mean of its divisors is an integer number (5064547800).

Almost surely, 2^20123136443 is an apocalyptic number.

20123136443 is a deficient number, since it is larger than the sum of its proper divisors (135054757).

20123136443 is a wasteful number, since it uses less digits than its factorization.

20123136443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135054756.

The product of its (nonzero) digits is 10368, while the sum is 29.

Adding to 20123136443 its reverse (34463132102), we get a palindrome (54586268545).

The spelling of 20123136443 in words is "twenty billion, one hundred twenty-three million, one hundred thirty-six thousand, four hundred forty-three".