21333232121 has 2 divisors, whose sum is σ = 21333232122. Its totient is φ = 21333232120.

The previous prime is 21333232103. The next prime is 21333232139. The reversal of 21333232121 is 12123233312.

It is a balanced prime because it is at equal distance from previous prime (21333232103) and next prime (21333232139).

It can be written as a sum of positive squares in only one way, i.e., 17740908025 + 3592324096 = 133195^2 + 59936^2 .

It is a cyclic number.

It is not a de Polignac number, because 21333232121 - 2⁶ = 21333232057 is a prime.

It is not a weakly prime, because it can be changed into another prime (21333232181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10666616060 + 10666616061.

It is an arithmetic number, because the mean of its divisors is an integer number (10666616061).

Almost surely, 2^21333232121 is an apocalyptic number.

It is an amenable number.

21333232121 is a deficient number, since it is larger than the sum of its proper divisors (1).

21333232121 is an equidigital number, since it uses as much as digits as its factorization.

21333232121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1296, while the sum is 23.

Adding to 21333232121 its reverse (12123233312), we get a palindrome (33456465433).

The spelling of 21333232121 in words is "twenty-one billion, three hundred thirty-three million, two hundred thirty-two thousand, one hundred twenty-one".