809185428 has 36 divisors (see below), whose sum is σ = 2061067008. Its totient is φ = 267667920.

The previous prime is 809185427. The next prime is 809185457. The reversal of 809185428 is 824581908.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809185423) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 81076 + ... + 90507.

Almost surely, 2^809185428 is an apocalyptic number.

It is an amenable number.

809185428 is an abundant number, since it is smaller than the sum of its proper divisors (1251881580).

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

809185428 is a wasteful number, since it uses less digits than its factorization.

809185428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171724 (or 171719 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 45.

The square root of 809185428 is about 28446.1847705452. The cubic root of 809185428 is about 931.8571698699.

The spelling of 809185428 in words is "eight hundred nine million, one hundred eighty-five thousand, four hundred twenty-eight".