851999221963 has 4 divisors (see below), whose sum is σ = 875026228000. Its totient is φ = 828972215928.

The previous prime is 851999221937. The next prime is 851999221967. The reversal of 851999221963 is 369122999158.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-851999221963 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 851999221895 and 851999221904.

It is not an unprimeable number, because it can be changed into a prime (851999221967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11513502963 + ... + 11513503036.

It is an arithmetic number, because the mean of its divisors is an integer number (218756557000).

Almost surely, 2^851999221963 is an apocalyptic number.

851999221963 is a deficient number, since it is larger than the sum of its proper divisors (23027006037).

851999221963 is a wasteful number, since it uses less digits than its factorization.

851999221963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23027006036.

The product of its digits is 18895680, while the sum is 64.

The spelling of 851999221963 in words is "eight hundred fifty-one billion, nine hundred ninety-nine million, two hundred twenty-one thousand, nine hundred sixty-three".