81860618 has 8 divisors (see below), whose sum is σ = 140332512. Its totient is φ = 35083116.

The previous prime is 81860599. The next prime is 81860663. The reversal of 81860618 is 81606818.

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, 2923580 + ... + 2923607.

It is an arithmetic number, because the mean of its divisors is an integer number (17541564).

Almost surely, 2^81860618 is an apocalyptic number.

81860618 is a deficient number, since it is larger than the sum of its proper divisors (58471894).

81860618 is a wasteful number, since it uses less digits than its factorization.

81860618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5847196.

The product of its (nonzero) digits is 18432, while the sum is 38.

The square root of 81860618 is about 9047.6857814582. The cubic root of 81860618 is about 434.2018534796.

The spelling of 81860618 in words is "eighty-one million, eight hundred sixty thousand, six hundred eighteen".