815433728 has 36 divisors (see below), whose sum is σ = 1633057335. Its totient is φ = 407070720.

The previous prime is 815433721. The next prime is 815433733. The reversal of 815433728 is 827334518.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 407716864 + 407716864 = 20192^2 + 20192^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=20192.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (815433721) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1291973 + ... + 1292603.

Almost surely, 2^815433728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 815433728

815433728 is an abundant number, since it is smaller than the sum of its proper divisors (817623607).

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

815433728 is an frugal number, since it uses more digits than its factorization.

815433728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1284 (or 633 counting only the distinct ones).

The product of its digits is 161280, while the sum is 41.

The square root of 815433728 is about 28555.8002514375. The cubic root of 815433728 is about 934.2495347888.

The spelling of 815433728 in words is "eight hundred fifteen million, four hundred thirty-three thousand, seven hundred twenty-eight".