12730315781 has 4 divisors (see below), whose sum is σ = 12823237932. Its totient is φ = 12637393632.

The previous prime is 12730315769. The next prime is 12730315813. The reversal of 12730315781 is 18751303721.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2608144900 + 10122170881 = 51070^2 + 100609^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12730315781 is a prime.

It is a super-2 number, since 2×12730315781² (a number of 21 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 (12730315181) 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, 46460870 + ... + 46461143.

It is an arithmetic number, because the mean of its divisors is an integer number (3205809483).

Almost surely, 2^12730315781 is an apocalyptic number.

It is an amenable number.

12730315781 is a deficient number, since it is larger than the sum of its proper divisors (92922151).

12730315781 is an equidigital number, since it uses as much as digits as its factorization.

12730315781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92922150.

The product of its (nonzero) digits is 35280, while the sum is 38.

The spelling of 12730315781 in words is "twelve billion, seven hundred thirty million, three hundred fifteen thousand, seven hundred eighty-one".