68640618 has 16 divisors (see below), whose sum is σ = 139872096. Its totient is φ = 22448400.

The previous prime is 68640617. The next prime is 68640619. The reversal of 68640618 is 81604686.

It is an interprime number because it is at equal distance from previous prime (68640617) and next prime (68640619).

It is not an unprimeable number, because it can be changed into a prime (68640613) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107608 + ... + 108243.

It is an arithmetic number, because the mean of its divisors is an integer number (8742006).

Almost surely, 2^68640618 is an apocalyptic number.

68640618 is an abundant number, since it is smaller than the sum of its proper divisors (71231478).

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

68640618 is a wasteful number, since it uses less digits than its factorization.

68640618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215909.

The product of its (nonzero) digits is 55296, while the sum is 39.

The square root of 68640618 is about 8284.9633674507. The cubic root of 68640618 is about 409.4432617984.

The spelling of 68640618 in words is "sixty-eight million, six hundred forty thousand, six hundred eighteen".