851720427 has 20 divisors (see below), whose sum is σ = 1306714816. Its totient is φ = 552465360.

The previous prime is 851720423. The next prime is 851720449. The reversal of 851720427 is 724027158.

851720427 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 851720427 - 2² = 851720423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 851720391 and 851720400.

It is not an unprimeable number, because it can be changed into a prime (851720423) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 139099 + ... + 145092.

Almost surely, 2^851720427 is an apocalyptic number.

851720427 is a deficient number, since it is larger than the sum of its proper divisors (454994389).

851720427 is a wasteful number, since it uses less digits than its factorization.

851720427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284240 (or 284231 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The square root of 851720427 is about 29184.2496391461. The cubic root of 851720427 is about 947.9069068176.

The spelling of 851720427 in words is "eight hundred fifty-one million, seven hundred twenty thousand, four hundred twenty-seven".