851493778 has 16 divisors (see below), whose sum is σ = 1345032000. Its totient is φ = 403168752.

The previous prime is 851493767. The next prime is 851493793. The reversal of 851493778 is 877394158.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 175408 + ... + 180196.

It is an arithmetic number, because the mean of its divisors is an integer number (84064500).

Almost surely, 2^851493778 is an apocalyptic number.

851493778 is a deficient number, since it is larger than the sum of its proper divisors (493538222).

851493778 is a wasteful number, since it uses less digits than its factorization.

851493778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9489.

The product of its digits is 1693440, while the sum is 52.

The square root of 851493778 is about 29180.3663102436. The cubic root of 851493778 is about 947.8228177176.

The spelling of 851493778 in words is "eight hundred fifty-one million, four hundred ninety-three thousand, seven hundred seventy-eight".