12660443531 has 4 divisors (see below), whose sum is σ = 12660669000. Its totient is φ = 12660218064.

The previous prime is 12660443501. The next prime is 12660443539. The reversal of 12660443531 is 13534406621.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 13534406621 = 15107 ⋅895903.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12660443531 is a prime.

It is a super-2 number, since 2×12660443531² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12660443491 and 12660443500.

It is not an unprimeable number, because it can be changed into a prime (12660443539) 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, 45920 + ... + 165618.

It is an arithmetic number, because the mean of its divisors is an integer number (3165167250).

Almost surely, 2^12660443531 is an apocalyptic number.

12660443531 is a deficient number, since it is larger than the sum of its proper divisors (225469).

12660443531 is a wasteful number, since it uses less digits than its factorization.

12660443531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225468.

The product of its (nonzero) digits is 51840, while the sum is 35.

The spelling of 12660443531 in words is "twelve billion, six hundred sixty million, four hundred forty-three thousand, five hundred thirty-one".