823136121 has 16 divisors (see below), whose sum is σ = 1272481920. Its totient is φ = 524898000.

The previous prime is 823136117. The next prime is 823136129. The reversal of 823136121 is 121631328.

It is a happy number.

It is not a de Polignac number, because 823136121 - 2² = 823136117 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (823136129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 662130 + ... + 663371.

It is an arithmetic number, because the mean of its divisors is an integer number (79530120).

Almost surely, 2^823136121 is an apocalyptic number.

It is an amenable number.

823136121 is a deficient number, since it is larger than the sum of its proper divisors (449345799).

823136121 is a wasteful number, since it uses less digits than its factorization.

823136121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1325533 (or 1325527 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 823136121 is about 28690.3489173624. The cubic root of 823136121 is about 937.1818875903.

Adding to 823136121 its reverse (121631328), we get a palindrome (944767449).

The spelling of 823136121 in words is "eight hundred twenty-three million, one hundred thirty-six thousand, one hundred twenty-one".