11726940681 has 9 divisors (see below), whose sum is σ = 16939383591. Its totient is φ = 7817743872.

The previous prime is 11726940613. The next prime is 11726940689. The reversal of 11726940681 is 18604962711.

The square root of 11726940681 is 108291.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1883126025 + 9843814656 = 43395^2 + 99216^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 11726940681 - 2²⁵ = 11693386249 is a prime.

It is a super-2 number, since 2×11726940681² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11726940689) 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 8 ways as a sum of consecutive naturals, for example, 306825 + ... + 342921.

Almost surely, 2^11726940681 is an apocalyptic number.

11726940681 is the 108291-st square number.

11726940681 is the 54146-th centered octagonal number.

It is an amenable number.

11726940681 is a deficient number, since it is larger than the sum of its proper divisors (5212442910).

11726940681 is an frugal number, since it uses more digits than its factorization.

11726940681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72200 (or 36100 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The spelling of 11726940681 in words is "eleven billion, seven hundred twenty-six million, nine hundred forty thousand, six hundred eighty-one".