861814915 has 64 divisors (see below), whose sum is σ = 1228639104. Its totient is φ = 574414848.

The previous prime is 861814913. The next prime is 861814963. The reversal of 861814915 is 519418168.

It is a cyclic number.

It is not a de Polignac number, because 861814915 - 2¹ = 861814913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861814913) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4374597 + ... + 4374793.

It is an arithmetic number, because the mean of its divisors is an integer number (19197486).

Almost surely, 2^861814915 is an apocalyptic number.

861814915 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

861814915 is a deficient number, since it is larger than the sum of its proper divisors (366824189).

861814915 is a wasteful number, since it uses less digits than its factorization.

861814915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376.

The product of its digits is 69120, while the sum is 43.

The square root of 861814915 is about 29356.6843325332. The cubic root of 861814915 is about 951.6370352511.

The spelling of 861814915 in words is "eight hundred sixty-one million, eight hundred fourteen thousand, nine hundred fifteen".