851866641 has 12 divisors (see below), whose sum is σ = 1235379600. Its totient is φ = 565647000.

The previous prime is 851866627. The next prime is 851866661. The reversal of 851866641 is 146668158.

It is not a de Polignac number, because 851866641 - 2¹⁰ = 851865617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (851866601) 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 11 ways as a sum of consecutive naturals, for example, 186291 + ... + 190808.

It is an arithmetic number, because the mean of its divisors is an integer number (102948300).

Almost surely, 2^851866641 is an apocalyptic number.

It is an amenable number.

851866641 is a deficient number, since it is larger than the sum of its proper divisors (383512959).

851866641 is a wasteful number, since it uses less digits than its factorization.

851866641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377356 (or 377353 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 851866641 is about 29186.7545472257. The cubic root of 851866641 is about 947.9611457931.

The spelling of 851866641 in words is "eight hundred fifty-one million, eight hundred sixty-six thousand, six hundred forty-one".