23181321533 has 8 divisors (see below), whose sum is σ = 24555323520. Its totient is φ = 21808474560.

The previous prime is 23181321523. The next prime is 23181321539. The reversal of 23181321533 is 33512318132.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 23181321533 - 2⁴ = 23181321517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23181321533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23181321539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 247253 + ... + 327866.

It is an arithmetic number, because the mean of its divisors is an integer number (3069415440).

Almost surely, 2^23181321533 is an apocalyptic number.

It is an amenable number.

23181321533 is a deficient number, since it is larger than the sum of its proper divisors (1374001987).

23181321533 is a wasteful number, since it uses less digits than its factorization.

23181321533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577507.

The product of its digits is 12960, while the sum is 32.

Adding to 23181321533 its reverse (33512318132), we get a palindrome (56693639665).

The spelling of 23181321533 in words is "twenty-three billion, one hundred eighty-one million, three hundred twenty-one thousand, five hundred thirty-three".