12787634813 has 4 divisors (see below), whose sum is σ = 12788573340. Its totient is φ = 12786696288.

The previous prime is 12787634803. The next prime is 12787634833. The reversal of 12787634813 is 31843678721.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4416665764 + 8370969049 = 66458^2 + 91493^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12787634813 is a prime.

It is a super-2 number, since 2×12787634813² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12787634803) 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, 448520 + ... + 476177.

It is an arithmetic number, because the mean of its divisors is an integer number (3197143335).

Almost surely, 2^12787634813 is an apocalyptic number.

It is an amenable number.

12787634813 is a deficient number, since it is larger than the sum of its proper divisors (938527).

12787634813 is an equidigital number, since it uses as much as digits as its factorization.

12787634813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 938526.

The product of its digits is 1354752, while the sum is 50.

The spelling of 12787634813 in words is "twelve billion, seven hundred eighty-seven million, six hundred thirty-four thousand, eight hundred thirteen".