11690661943921 has 9 divisors (see below), whose sum is σ = 11706963250849. Its totient is φ = 11674383318400.

The previous prime is 11690661943907. The next prime is 11690661943979. The reversal of 11690661943921 is 12934916609611.

The square root of 11690661943921 is 3419161.

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

It can be written as a sum of positive squares in 4 ways, for example, as 564167734321 + 11126494209600 = 751111^2 + 3335640^2 .

It is a de Polignac number, because none of the positive numbers 2^k-11690661943921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11690661943901) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3012278901 + ... + 3012282781.

Almost surely, 2^{11690661943921} is an apocalyptic number.

11690661943921 is the 3419161-st square number.

11690661943921 is the 1709581-st centered octagonal number.

It is an amenable number.

11690661943921 is a deficient number, since it is larger than the sum of its proper divisors (16301306928).

11690661943921 is an frugal number, since it uses more digits than its factorization.

11690661943921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9524 (or 4762 counting only the distinct ones).

The product of its (nonzero) digits is 3779136, while the sum is 58.

The spelling of 11690661943921 in words is "eleven trillion, six hundred ninety billion, six hundred sixty-one million, nine hundred forty-three thousand, nine hundred twenty-one".