142821685 has 4 divisors (see below), whose sum is σ = 171386028. Its totient is φ = 114257344.

The previous prime is 142821677. The next prime is 142821821. The reversal of 142821685 is 586128241.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 586128241 = 127 ⋅4615183.

It can be written as a sum of positive squares in 2 ways, for example, as 35533521 + 107288164 = 5961^2 + 10358^2 .

It is a cyclic number.

It is not a de Polignac number, because 142821685 - 2³ = 142821677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14282164 + ... + 14282173.

It is an arithmetic number, because the mean of its divisors is an integer number (42846507).

Almost surely, 2^142821685 is an apocalyptic number.

It is an amenable number.

142821685 is a deficient number, since it is larger than the sum of its proper divisors (28564343).

142821685 is an equidigital number, since it uses as much as digits as its factorization.

142821685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28564342.

The product of its digits is 30720, while the sum is 37.

The square root of 142821685 is about 11950.8026927065. The cubic root of 142821685 is about 522.7147046162.

The spelling of 142821685 in words is "one hundred forty-two million, eight hundred twenty-one thousand, six hundred eighty-five".