646883970 has 64 divisors (see below), whose sum is σ = 1623386880. Its totient is φ = 164659968.

The previous prime is 646883933. The next prime is 646883999. The reversal of 646883970 is 79388646.

It is a Curzon number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 604596 + ... + 605664.

It is an arithmetic number, because the mean of its divisors is an integer number (25365420).

Almost surely, 2^646883970 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646883970, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (811693440).

646883970 is an abundant number, since it is smaller than the sum of its proper divisors (976502910).

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

646883970 is a wasteful number, since it uses less digits than its factorization.

646883970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1979.

The product of its (nonzero) digits is 1741824, while the sum is 51.

The square root of 646883970 is about 25433.9137766880. The cubic root of 646883970 is about 864.8526685042.

The spelling of 646883970 in words is "six hundred forty-six million, eight hundred eighty-three thousand, nine hundred seventy".