78219618 has 32 divisors (see below), whose sum is σ = 174363840. Its totient is φ = 23247360.

The previous prime is 78219613. The next prime is 78219643. The reversal of 78219618 is 81691287.

It is a super-2 number, since 2×78219618² = 12236617280131848, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78219618.

It is not an unprimeable number, because it can be changed into a prime (78219611) 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 15 ways as a sum of consecutive naturals, for example, 18243 + ... + 22118.

It is an arithmetic number, because the mean of its divisors is an integer number (5448870).

Almost surely, 2^78219618 is an apocalyptic number.

78219618 is an abundant number, since it is smaller than the sum of its proper divisors (96144222).

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

78219618 is a wasteful number, since it uses less digits than its factorization.

78219618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40402.

The product of its digits is 48384, while the sum is 42.

The square root of 78219618 is about 8844.1855475787. The cubic root of 78219618 is about 427.6664978489. Note that the first 3 decimals are identical.

The spelling of 78219618 in words is "seventy-eight million, two hundred nineteen thousand, six hundred eighteen".