815478016189 has 4 divisors (see below), whose sum is σ = 815482866780. Its totient is φ = 815473165600.

The previous prime is 815478016159. The next prime is 815478016211. The reversal of 815478016189 is 981610874518.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 981610874518 = 2 ⋅490805437259.

It can be written as a sum of positive squares in 2 ways, for example, as 409141888164 + 406336128025 = 639642^2 + 637445^2 .

It is a cyclic number.

It is not a de Polignac number, because 815478016189 - 2¹⁵ = 815477983421 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (815478016109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2163712 + ... + 2512489.

It is an arithmetic number, because the mean of its divisors is an integer number (203870716695).

Almost surely, 2^815478016189 is an apocalyptic number.

It is an amenable number.

815478016189 is a deficient number, since it is larger than the sum of its proper divisors (4850591).

815478016189 is a wasteful number, since it uses less digits than its factorization.

815478016189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4850590.

The product of its (nonzero) digits is 3870720, while the sum is 58.

The spelling of 815478016189 in words is "eight hundred fifteen billion, four hundred seventy-eight million, sixteen thousand, one hundred eighty-nine".