646040140 has 12 divisors (see below), whose sum is σ = 1356684336. Its totient is φ = 258416048.

The previous prime is 646040107. The next prime is 646040141. The reversal of 646040140 is 41040646.

It is not an unprimeable number, because it can be changed into a prime (646040141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16150984 + ... + 16151023.

It is an arithmetic number, because the mean of its divisors is an integer number (113057028).

Almost surely, 2^646040140 is an apocalyptic number.

It is an amenable number.

646040140 is an abundant number, since it is smaller than the sum of its proper divisors (710644196).

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

646040140 is a wasteful number, since it uses less digits than its factorization.

646040140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32302016 (or 32302014 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 646040140 is about 25417.3196856002. The cubic root of 646040140 is about 864.4764515336.

Adding to 646040140 its reverse (41040646), we get a palindrome (687080786).

The spelling of 646040140 in words is "six hundred forty-six million, forty thousand, one hundred forty".