21523465121 has 8 divisors (see below), whose sum is σ = 21748285440. Its totient is φ = 21298704768.

The previous prime is 21523465099. The next prime is 21523465123. The reversal of 21523465121 is 12156432512.

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 21523465121 - 2³⁰ = 20449723297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21523465123) 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 7 ways as a sum of consecutive naturals, for example, 1326560 + ... + 1342686.

It is an arithmetic number, because the mean of its divisors is an integer number (2718535680).

Almost surely, 2^21523465121 is an apocalyptic number.

It is an amenable number.

21523465121 is a deficient number, since it is larger than the sum of its proper divisors (224820319).

21523465121 is a wasteful number, since it uses less digits than its factorization.

21523465121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29983.

The product of its digits is 14400, while the sum is 32.

Adding to 21523465121 its reverse (12156432512), we get a palindrome (33679897633).

The spelling of 21523465121 in words is "twenty-one billion, five hundred twenty-three million, four hundred sixty-five thousand, one hundred twenty-one".