851864819 has 8 divisors (see below), whose sum is σ = 924618240. Its totient is φ = 780143616.

The previous prime is 851864807. The next prime is 851864861. The reversal of 851864819 is 918468158.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 851864819 - 2²⁰ = 850816243 is a prime.

It is a super-2 number, since 2×851864819² = 1451347339699805522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (851864119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 256334 + ... + 259635.

It is an arithmetic number, because the mean of its divisors is an integer number (115577280).

Almost surely, 2^851864819 is an apocalyptic number.

851864819 is a deficient number, since it is larger than the sum of its proper divisors (72753421).

851864819 is a wasteful number, since it uses less digits than its factorization.

851864819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516109.

The product of its digits is 552960, while the sum is 50.

The square root of 851864819 is about 29186.7233344204. The cubic root of 851864819 is about 947.9604699493.

It can be divided in two parts, 8518 and 64819, that added together give a palindrome (73337).

The spelling of 851864819 in words is "eight hundred fifty-one million, eight hundred sixty-four thousand, eight hundred nineteen".