784520561 has 12 divisors (see below), whose sum is σ = 874146756. Its totient is φ = 703422720.

The previous prime is 784520551. The next prime is 784520563. The reversal of 784520561 is 165025487.

It can be written as a sum of positive squares in 2 ways, for example, as 390299536 + 394221025 = 19756^2 + 19855^2 .

It is not a de Polignac number, because 784520561 - 2¹⁰ = 784519537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (784520563) 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, 35576 + ... + 53241.

It is an arithmetic number, because the mean of its divisors is an integer number (72845563).

Almost surely, 2^784520561 is an apocalyptic number.

It is an amenable number.

784520561 is a deficient number, since it is larger than the sum of its proper divisors (89626195).

784520561 is a wasteful number, since it uses less digits than its factorization.

784520561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88912 (or 88901 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 784520561 is about 28009.2941896078. The cubic root of 784520561 is about 922.2912960252.

The spelling of 784520561 in words is "seven hundred eighty-four million, five hundred twenty thousand, five hundred sixty-one".