12644437497 has 16 divisors (see below), whose sum is σ = 17853244992. Its totient is φ = 7932753920.

The previous prime is 12644437439. The next prime is 12644437537. The reversal of 12644437497 is 79473444621.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 12644437497 - 2¹⁴ = 12644421113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (12644437097) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 734098 + ... + 751124.

It is an arithmetic number, because the mean of its divisors is an integer number (1115827812).

Almost surely, 2^12644437497 is an apocalyptic number.

12644437497 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

12644437497 is a deficient number, since it is larger than the sum of its proper divisors (5208807495).

12644437497 is a wasteful number, since it uses less digits than its factorization.

12644437497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31608.

The product of its digits is 4064256, while the sum is 51.

The spelling of 12644437497 in words is "twelve billion, six hundred forty-four million, four hundred thirty-seven thousand, four hundred ninety-seven".