865820018 has 16 divisors (see below), whose sum is σ = 1532143104. Its totient is φ = 359095680.

The previous prime is 865820009. The next prime is 865820051. The reversal of 865820018 is 810028568.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 997055 + ... + 997922.

It is an arithmetic number, because the mean of its divisors is an integer number (95758944).

Almost surely, 2^865820018 is an apocalyptic number.

865820018 is a deficient number, since it is larger than the sum of its proper divisors (666323086).

865820018 is a wasteful number, since it uses less digits than its factorization.

865820018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1995017.

The product of its (nonzero) digits is 30720, while the sum is 38.

The square root of 865820018 is about 29424.8197615550. The cubic root of 865820018 is about 953.1089349373.

The spelling of 865820018 in words is "eight hundred sixty-five million, eight hundred twenty thousand, eighteen".