646142240 has 48 divisors (see below), whose sum is σ = 1528450560. Its totient is φ = 258128640.

The previous prime is 646142227. The next prime is 646142257. The reversal of 646142240 is 42241646.

It is a happy 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 7 ways as a sum of consecutive naturals, for example, 153281 + ... + 157439.

It is an arithmetic number, because the mean of its divisors is an integer number (31842720).

Almost surely, 2^646142240 is an apocalyptic number.

It is an amenable number.

646142240 is an abundant number, since it is smaller than the sum of its proper divisors (882308320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646142240 is a wasteful number, since it uses less digits than its factorization.

646142240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5145 (or 5137 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 29.

The square root of 646142240 is about 25419.3280792392. The cubic root of 646142240 is about 864.5219896723.

Adding to 646142240 its reverse (42241646), we get a palindrome (688383886).

The spelling of 646142240 in words is "six hundred forty-six million, one hundred forty-two thousand, two hundred forty".