12645747521 has 16 divisors (see below), whose sum is σ = 14665233600. Its totient is φ = 10783224000.

The previous prime is 12645747503. The next prime is 12645747529. The reversal of 12645747521 is 12574754621.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12645747521 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12645747529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 278426 + ... + 320643.

It is an arithmetic number, because the mean of its divisors is an integer number (916577100).

Almost surely, 2^12645747521 is an apocalyptic number.

12645747521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12645747521 is a deficient number, since it is larger than the sum of its proper divisors (2019486079).

12645747521 is a wasteful number, since it uses less digits than its factorization.

12645747521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599200.

The product of its digits is 470400, while the sum is 44.

The spelling of 12645747521 in words is "twelve billion, six hundred forty-five million, seven hundred forty-seven thousand, five hundred twenty-one".