12736649381 has 4 divisors (see below), whose sum is σ = 12890103072. Its totient is φ = 12583195692.

The previous prime is 12736649371. The next prime is 12736649413. The reversal of 12736649381 is 18394663721.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12736649381 - 2¹⁰ = 12736648357 is a prime.

It is a super-2 number, since 2×12736649381² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12736649351) 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 3 ways as a sum of consecutive naturals, for example, 76726721 + ... + 76726886.

It is an arithmetic number, because the mean of its divisors is an integer number (3222525768).

Almost surely, 2^12736649381 is an apocalyptic number.

It is an amenable number.

12736649381 is a deficient number, since it is larger than the sum of its proper divisors (153453691).

12736649381 is an equidigital number, since it uses as much as digits as its factorization.

12736649381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153453690.

The product of its digits is 1306368, while the sum is 50.

The spelling of 12736649381 in words is "twelve billion, seven hundred thirty-six million, six hundred forty-nine thousand, three hundred eighty-one".