42857221865 has 8 divisors (see below), whose sum is σ = 51556919688. Its totient is φ = 34200275200.

The previous prime is 42857221859. The next prime is 42857221909. The reversal of 42857221865 is 56812275824.

It can be written as a sum of positive squares in 4 ways, for example, as 14667147664 + 28190074201 = 121108^2 + 167899^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 42857221865 - 2¹⁴ = 42857205481 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10685582 + ... + 10689591.

It is an arithmetic number, because the mean of its divisors is an integer number (6444614961).

Almost surely, 2^42857221865 is an apocalyptic number.

It is an amenable number.

42857221865 is a deficient number, since it is larger than the sum of its proper divisors (8699697823).

42857221865 is a wasteful number, since it uses less digits than its factorization.

42857221865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21375579.

The product of its digits is 2150400, while the sum is 50.

The spelling of 42857221865 in words is "forty-two billion, eight hundred fifty-seven million, two hundred twenty-one thousand, eight hundred sixty-five".