642283281 has 6 divisors (see below), whose sum is σ = 927742530. Its totient is φ = 428188848.

The previous prime is 642283261. The next prime is 642283283. The reversal of 642283281 is 182382246.

642283281 is a `hidden beast` number, since 642 + 2 + 8 + 3 + 2 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 571975056 + 70308225 = 23916^2 + 8385^2 .

It is not a de Polignac number, because 642283281 - 2¹³ = 642275089 is a prime.

It is a super-2 number, since 2×642283281² = 825055626104249922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (642283283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35682396 + ... + 35682413.

It is an arithmetic number, because the mean of its divisors is an integer number (154623755).

Almost surely, 2^642283281 is an apocalyptic number.

It is an amenable number.

642283281 is a deficient number, since it is larger than the sum of its proper divisors (285459249).

642283281 is a wasteful number, since it uses less digits than its factorization.

642283281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71364815 (or 71364812 counting only the distinct ones).

The product of its digits is 36864, while the sum is 36.

The square root of 642283281 is about 25343.3084067570. The cubic root of 642283281 is about 862.7974888104.

The spelling of 642283281 in words is "six hundred forty-two million, two hundred eighty-three thousand, two hundred eighty-one".