645989683 has 8 divisors (see below), whose sum is σ = 681195600. Its totient is φ = 610904448.

The previous prime is 645989677. The next prime is 645989693. The reversal of 645989683 is 386989546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645989683 - 2⁵ = 645989651 is a prime.

It is not an unprimeable number, because it can be changed into a prime (645989633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19066 + ... + 40687.

It is an arithmetic number, because the mean of its divisors is an integer number (85149450).

Almost surely, 2^645989683 is an apocalyptic number.

645989683 is a deficient number, since it is larger than the sum of its proper divisors (35205917).

645989683 is a wasteful number, since it uses less digits than its factorization.

645989683 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60341.

The product of its digits is 11197440, while the sum is 58.

The square root of 645989683 is about 25416.3270949994. The cubic root of 645989683 is about 864.4539451798.

The spelling of 645989683 in words is "six hundred forty-five million, nine hundred eighty-nine thousand, six hundred eighty-three".