12538565505 has 96 divisors (see below), whose sum is σ = 23348183040. Its totient is φ = 6448559040.

The previous prime is 12538565503. The next prime is 12538565537. The reversal of 12538565505 is 50556583521.

It is a happy number.

12538565505 is a `hidden beast` number, since 1 + 2 + 5 + 3 + 85 + 65 + 505 = 666.

It is not a de Polignac number, because 12538565505 - 2¹ = 12538565503 is a prime.

It is a super-3 number, since 3×12538565505³ (a number of 31 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (12538565503) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 17438536 + ... + 17439254.

It is an arithmetic number, because the mean of its divisors is an integer number (243210240).

Almost surely, 2^12538565505 is an apocalyptic number.

12538565505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12538565505 is a deficient number, since it is larger than the sum of its proper divisors (10809617535).

12538565505 is an equidigital number, since it uses as much as digits as its factorization.

12538565505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1233 (or 1221 counting only the distinct ones).

The product of its (nonzero) digits is 900000, while the sum is 45.

The spelling of 12538565505 in words is "twelve billion, five hundred thirty-eight million, five hundred sixty-five thousand, five hundred five".