645489868 has 12 divisors (see below), whose sum is σ = 1137734920. Its totient is φ = 320422752.

The previous prime is 645489853. The next prime is 645489883. The reversal of 645489868 is 868984546.

645489868 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (645489853) and next prime (645489883).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 579921 + ... + 581032.

Almost surely, 2^645489868 is an apocalyptic number.

It is an amenable number.

645489868 is a deficient number, since it is larger than the sum of its proper divisors (492245052).

645489868 is a wasteful number, since it uses less digits than its factorization.

645489868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1161096 (or 1161094 counting only the distinct ones).

The product of its digits is 13271040, while the sum is 58.

The square root of 645489868 is about 25406.4926347578. The cubic root of 645489868 is about 864.2309392811.

The spelling of 645489868 in words is "six hundred forty-five million, four hundred eighty-nine thousand, eight hundred sixty-eight".