648689618 has 8 divisors (see below), whose sum is σ = 996767100. Its totient is φ = 316433920.

The previous prime is 648689609. The next prime is 648689627. The reversal of 648689618 is 816986846.

It is an interprime number because it is at equal distance from previous prime (648689609) and next prime (648689627).

It can be written as a sum of positive squares in 2 ways, for example, as 509991889 + 138697729 = 22583^2 + 11777^2 .

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

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, 3955343 + ... + 3955506.

Almost surely, 2^648689618 is an apocalyptic number.

648689618 is a deficient number, since it is larger than the sum of its proper divisors (348077482).

648689618 is a wasteful number, since it uses less digits than its factorization.

648689618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7910892.

The product of its digits is 3981312, while the sum is 56.

The square root of 648689618 is about 25469.3858975830. The cubic root of 648689618 is about 865.6566090505.

The spelling of 648689618 in words is "six hundred forty-eight million, six hundred eighty-nine thousand, six hundred eighteen".