23121553 has 8 divisors (see below), whose sum is σ = 28457408. Its totient is φ = 18293904.

The previous prime is 23121521. The next prime is 23121557. The reversal of 23121553 is 35512132.

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 23121553 - 2⁵ = 23121521 is a prime.

It is a super-3 number, since 3×23121553³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (23121557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126951 + ... + 127132.

It is an arithmetic number, because the mean of its divisors is an integer number (3557176).

Almost surely, 2^23121553 is an apocalyptic number.

It is an amenable number.

23121553 is a deficient number, since it is larger than the sum of its proper divisors (5335855).

23121553 is a wasteful number, since it uses less digits than its factorization.

23121553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254103.

The product of its digits is 900, while the sum is 22.

The square root of 23121553 is about 4808.4876000672. The cubic root of 23121553 is about 284.8868043341.

Adding to 23121553 its reverse (35512132), we get a palindrome (58633685).

The spelling of 23121553 in words is "twenty-three million, one hundred twenty-one thousand, five hundred fifty-three".