8148320781 has 4 divisors (see below), whose sum is σ = 10864427712. Its totient is φ = 5432213852.

The previous prime is 8148320773. The next prime is 8148320797. The reversal of 8148320781 is 1870238418.

8148320781 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 8148320781 - 2³ = 8148320773 is a prime.

It is a super-2 number, since 2×8148320781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8148325781) 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, 1358053461 + ... + 1358053466.

It is an arithmetic number, because the mean of its divisors is an integer number (2716106928).

Almost surely, 2^8148320781 is an apocalyptic number.

It is an amenable number.

8148320781 is a deficient number, since it is larger than the sum of its proper divisors (2716106931).

8148320781 is a wasteful number, since it uses less digits than its factorization.

8148320781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2716106930.

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 8148320781 is about 90268.0496133599. The cubic root of 8148320781 is about 2012.2844566605.

The spelling of 8148320781 in words is "eight billion, one hundred forty-eight million, three hundred twenty thousand, seven hundred eighty-one".