8127325781 has 4 divisors (see below), whose sum is σ = 8199249132. Its totient is φ = 8055402432.

The previous prime is 8127325727. The next prime is 8127325837. The reversal of 8127325781 is 1875237218.

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 378925156 + 7748400625 = 19466^2 + 88025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8127325781 is a prime.

It is a super-2 number, since 2×8127325781² (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 (8127345781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35961506 + ... + 35961731.

It is an arithmetic number, because the mean of its divisors is an integer number (2049812283).

Almost surely, 2^8127325781 is an apocalyptic number.

It is an amenable number.

8127325781 is a deficient number, since it is larger than the sum of its proper divisors (71923351).

8127325781 is a wasteful number, since it uses less digits than its factorization.

8127325781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71923350.

The product of its digits is 188160, while the sum is 44.

The square root of 8127325781 is about 90151.6820752669. The cubic root of 8127325781 is about 2010.5546830985.

The spelling of 8127325781 in words is "eight billion, one hundred twenty-seven million, three hundred twenty-five thousand, seven hundred eighty-one".