21320000121 has 32 divisors (see below), whose sum is σ = 34070630400. Its totient is φ = 11594556864.

The previous prime is 21320000099. The next prime is 21320000129. The reversal of 21320000121 is 12100002312.

It is not a de Polignac number, because 21320000121 - 2¹⁵ = 21319967353 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21320000097 and 21320000106.

It is not an unprimeable number, because it can be changed into a prime (21320000129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14790 + ... + 207023.

It is an arithmetic number, because the mean of its divisors is an integer number (1064707200).

Almost surely, 2^21320000121 is an apocalyptic number.

21320000121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21320000121 is a deficient number, since it is larger than the sum of its proper divisors (12750630279).

21320000121 is a wasteful number, since it uses less digits than its factorization.

21320000121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222045.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21320000121 its reverse (12100002312), we get a palindrome (33420002433).

The spelling of 21320000121 in words is "twenty-one billion, three hundred twenty million, one hundred twenty-one", and thus it is an aban number.