823245561 has 12 divisors (see below), whose sum is σ = 1214433792. Its totient is φ = 537152856.

The previous prime is 823245559. The next prime is 823245581. The reversal of 823245561 is 165542328.

823245561 is a `hidden beast` number, since 82 + 3 + 24 + 556 + 1 = 666.

It is not a de Polignac number, because 823245561 - 2¹ = 823245559 is a prime.

It is not an unprimeable number, because it can be changed into a prime (823245551) 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, 972681 + ... + 973526.

It is an arithmetic number, because the mean of its divisors is an integer number (101202816).

Almost surely, 2^823245561 is an apocalyptic number.

It is an amenable number.

823245561 is a deficient number, since it is larger than the sum of its proper divisors (391188231).

823245561 is a wasteful number, since it uses less digits than its factorization.

823245561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1946260 (or 1946257 counting only the distinct ones).

The product of its digits is 57600, while the sum is 36.

The square root of 823245561 is about 28692.2561155445. The cubic root of 823245561 is about 937.2234200651.

Adding to 823245561 its reverse (165542328), we get a palindrome (988787889).

The spelling of 823245561 in words is "eight hundred twenty-three million, two hundred forty-five thousand, five hundred sixty-one".