646344040 has 32 divisors (see below), whose sum is σ = 1461600000. Its totient is φ = 257235264.

The previous prime is 646344019. The next prime is 646344103. The reversal of 646344040 is 40443646.

It is a junction number, because it is equal to n+sod(n) for n = 646343993 and 646344011.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32640 + ... + 48559.

It is an arithmetic number, because the mean of its divisors is an integer number (45675000).

Almost surely, 2^646344040 is an apocalyptic number.

It is an amenable number.

646344040 is an abundant number, since it is smaller than the sum of its proper divisors (815255960).

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

646344040 is a wasteful number, since it uses less digits than its factorization.

646344040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81409 (or 81405 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 31.

The square root of 646344040 is about 25423.2971897824. The cubic root of 646344040 is about 864.6119814046.

Adding to 646344040 its reverse (40443646), we get a palindrome (686787686).

The spelling of 646344040 in words is "six hundred forty-six million, three hundred forty-four thousand, forty".