645800698 has 8 divisors (see below), whose sum is σ = 968827860. Its totient is φ = 322858080.

The previous prime is 645800689. The next prime is 645800713. The reversal of 645800698 is 896008546.

It can be written as a sum of positive squares in 2 ways, for example, as 635897089 + 9903609 = 25217^2 + 3147^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3888 + ... + 36148.

Almost surely, 2^645800698 is an apocalyptic number.

645800698 is a deficient number, since it is larger than the sum of its proper divisors (323027162).

645800698 is a wasteful number, since it uses less digits than its factorization.

645800698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42272.

The product of its (nonzero) digits is 414720, while the sum is 46.

The square root of 645800698 is about 25412.6090356736. The cubic root of 645800698 is about 864.3696379703.

The spelling of 645800698 in words is "six hundred forty-five million, eight hundred thousand, six hundred ninety-eight".