20123234515 has 4 divisors (see below), whose sum is σ = 24147881424. Its totient is φ = 16098587608.

The previous prime is 20123234513. The next prime is 20123234581. The reversal of 20123234515 is 51543232102.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51543232102 = 2 ⋅25771616051.

It is a cyclic number.

It is not a de Polignac number, because 20123234515 - 2¹ = 20123234513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20123234513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2012323447 + ... + 2012323456.

It is an arithmetic number, because the mean of its divisors is an integer number (6036970356).

Almost surely, 2^20123234515 is an apocalyptic number.

20123234515 is a deficient number, since it is larger than the sum of its proper divisors (4024646909).

20123234515 is an equidigital number, since it uses as much as digits as its factorization.

20123234515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4024646908.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 20123234515 its reverse (51543232102), we get a palindrome (71666466617).

The spelling of 20123234515 in words is "twenty billion, one hundred twenty-three million, two hundred thirty-four thousand, five hundred fifteen".