851216905 has 32 divisors (see below), whose sum is σ = 1275533568. Its totient is φ = 529785600.

The previous prime is 851216881. The next prime is 851216963. The reversal of 851216905 is 509612158.

It is not a de Polignac number, because 851216905 - 2¹³ = 851208713 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 314739 + ... + 317431.

It is an arithmetic number, because the mean of its divisors is an integer number (39860424).

Almost surely, 2^851216905 is an apocalyptic number.

It is an amenable number.

851216905 is a deficient number, since it is larger than the sum of its proper divisors (424316663).

851216905 is a wasteful number, since it uses less digits than its factorization.

851216905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3537.

The product of its (nonzero) digits is 21600, while the sum is 37.

The square root of 851216905 is about 29175.6217585847. The cubic root of 851216905 is about 947.7200747489.

The spelling of 851216905 in words is "eight hundred fifty-one million, two hundred sixteen thousand, nine hundred five".