12720756681631 has 4 divisors (see below), whose sum is σ = 12728139594952. Its totient is φ = 12713373768312.

The previous prime is 12720756681629. The next prime is 12720756681671. The reversal of 12720756681631 is 13618665702721.

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

It is a cyclic number.

It is not a de Polignac number, because 12720756681631 - 2¹ = 12720756681629 is a prime.

It is a super-2 number, since 2×12720756681631² (a number of 27 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 (12720756681671) 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, 3691454076 + ... + 3691457521.

It is an arithmetic number, because the mean of its divisors is an integer number (3182034898738).

Almost surely, 2^{12720756681631} is an apocalyptic number.

12720756681631 is a deficient number, since it is larger than the sum of its proper divisors (7382913321).

12720756681631 is an equidigital number, since it uses as much as digits as its factorization.

12720756681631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7382913320.

The product of its (nonzero) digits is 5080320, while the sum is 55.

The spelling of 12720756681631 in words is "twelve trillion, seven hundred twenty billion, seven hundred fifty-six million, six hundred eighty-one thousand, six hundred thirty-one".