646694560 has 48 divisors (see below), whose sum is σ = 1532557152. Its totient is φ = 257875200.

The previous prime is 646694549. The next prime is 646694563. The reversal of 646694560 is 65496646.

It is a self number, because there is not a number n which added to its sum of digits gives 646694560.

It is not an unprimeable number, because it can be changed into a prime (646694563) 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 7 ways as a sum of consecutive naturals, for example, 46855 + ... + 59065.

It is an arithmetic number, because the mean of its divisors is an integer number (31928274).

Almost surely, 2^646694560 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646694560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (766278576).

646694560 is an abundant number, since it is smaller than the sum of its proper divisors (885862592).

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

646694560 is a wasteful number, since it uses less digits than its factorization.

646694560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12557 (or 12549 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 46.

The square root of 646694560 is about 25430.1899324405. The cubic root of 646694560 is about 864.7682495860.

The spelling of 646694560 in words is "six hundred forty-six million, six hundred ninety-four thousand, five hundred sixty".