851981826 has 24 divisors (see below), whose sum is σ = 1810096560. Its totient is φ = 267287872.

The previous prime is 851981791. The next prime is 851981827. The reversal of 851981826 is 628189158.

It is not an unprimeable number, because it can be changed into a prime (851981827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 243936 + ... + 247403.

It is an arithmetic number, because the mean of its divisors is an integer number (75420690).

Almost surely, 2^851981826 is an apocalyptic number.

851981826 is an abundant number, since it is smaller than the sum of its proper divisors (958114734).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

851981826 is a wasteful number, since it uses less digits than its factorization.

851981826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491378 (or 491361 counting only the distinct ones).

The product of its digits is 276480, while the sum is 48.

The square root of 851981826 is about 29188.7277215024. The cubic root of 851981826 is about 948.0038700015.

The spelling of 851981826 in words is "eight hundred fifty-one million, nine hundred eighty-one thousand, eight hundred twenty-six".