642238585 has 4 divisors (see below), whose sum is σ = 770686308. Its totient is φ = 513790864.

The previous prime is 642238567. The next prime is 642238603. The reversal of 642238585 is 585832246.

642238585 is digitally balanced in base 2, 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: 585832246 = 2 ⋅292916123.

It is an interprime number because it is at equal distance from previous prime (642238567) and next prime (642238603).

It can be written as a sum of positive squares in 2 ways, for example, as 291350761 + 350887824 = 17069^2 + 18732^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-642238585 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64223854 + ... + 64223863.

It is an arithmetic number, because the mean of its divisors is an integer number (192671577).

Almost surely, 2^642238585 is an apocalyptic number.

It is an amenable number.

642238585 is a deficient number, since it is larger than the sum of its proper divisors (128447723).

642238585 is a wasteful number, since it uses less digits than its factorization.

642238585 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128447722.

The product of its digits is 460800, while the sum is 43.

The square root of 642238585 is about 25342.4265807361. The cubic root of 642238585 is about 862.7774745413. Note that the first 3 decimals are identical.

The spelling of 642238585 in words is "six hundred forty-two million, two hundred thirty-eight thousand, five hundred eighty-five".