13131010781 has 4 divisors (see below), whose sum is σ = 15006869472. Its totient is φ = 11255152092.

The previous prime is 13131010777. The next prime is 13131010811. The reversal of 13131010781 is 18701013131.

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, and also an emirpimes, since its reverse is a distinct semiprime: 18701013131 = 19 ⋅984263849.

It is a cyclic number.

It is not a de Polignac number, because 13131010781 - 2² = 13131010777 is a prime.

It is a super-3 number, since 3×13131010781³ (a number of 31 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 13131010781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13131010381) 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, 937929335 + ... + 937929348.

It is an arithmetic number, because the mean of its divisors is an integer number (3751717368).

Almost surely, 2^13131010781 is an apocalyptic number.

It is an amenable number.

13131010781 is a deficient number, since it is larger than the sum of its proper divisors (1875858691).

13131010781 is an equidigital number, since it uses as much as digits as its factorization.

13131010781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1875858690.

The product of its (nonzero) digits is 504, while the sum is 26.

The spelling of 13131010781 in words is "thirteen billion, one hundred thirty-one million, ten thousand, seven hundred eighty-one".