21023232121 has 8 divisors (see below), whose sum is σ = 22679891784. Its totient is φ = 19413239040.

The previous prime is 21023232107. The next prime is 21023232137. The reversal of 21023232121 is 12123232012.

It can be written as a sum of positive squares in 4 ways, for example, as 14256360000 + 6766872121 = 119400^2 + 82261^2 .

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 21023232121 - 2¹¹ = 21023230073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21023232151) 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, 11665710 + ... + 11667511.

It is an arithmetic number, because the mean of its divisors is an integer number (2834986473).

Almost surely, 2^21023232121 is an apocalyptic number.

It is an amenable number.

21023232121 is a deficient number, since it is larger than the sum of its proper divisors (1656659663).

21023232121 is a wasteful number, since it uses less digits than its factorization.

21023232121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23333291.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21023232121 its reverse (12123232012), we get a palindrome (33146464133).

The spelling of 21023232121 in words is "twenty-one billion, twenty-three million, two hundred thirty-two thousand, one hundred twenty-one".