8167142821 has 4 divisors (see below), whose sum is σ = 8175050092. Its totient is φ = 8159235552.

The previous prime is 8167142801. The next prime is 8167142843. The reversal of 8167142821 is 1282417618.

8167142821 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 an emirpimes, since its reverse is a distinct semiprime: 1282417618 = 2 ⋅641208809.

It can be written as a sum of positive squares in 2 ways, for example, as 4380586596 + 3786556225 = 66186^2 + 61535^2 .

It is a cyclic number.

It is not a de Polignac number, because 8167142821 - 2²³ = 8158754213 is a prime.

It is a super-2 number, since 2×8167142821² (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 (8167142801) 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, 3952086 + ... + 3954151.

It is an arithmetic number, because the mean of its divisors is an integer number (2043762523).

Almost surely, 2^8167142821 is an apocalyptic number.

It is an amenable number.

8167142821 is a deficient number, since it is larger than the sum of its proper divisors (7907271).

8167142821 is a wasteful number, since it uses less digits than its factorization.

8167142821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7907270.

The product of its digits is 43008, while the sum is 40.

The square root of 8167142821 is about 90372.2458556829. The cubic root of 8167142821 is about 2013.8326763833.

The spelling of 8167142821 in words is "eight billion, one hundred sixty-seven million, one hundred forty-two thousand, eight hundred twenty-one".