20121221127 has 8 divisors (see below), whose sum is σ = 30660908416. Its totient is φ = 11497840632.

The previous prime is 20121221117. The next prime is 20121221129. The reversal of 20121221127 is 72112212102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20121221127 - 2¹⁰ = 20121220103 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 958153387 = 20121221127 / (2 + 0 + 1 + 2 + 1 + 2 + 2 + 1 + 1 + 2 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121221129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 479076673 + ... + 479076714.

It is an arithmetic number, because the mean of its divisors is an integer number (3832613552).

Almost surely, 2^20121221127 is an apocalyptic number.

20121221127 is a deficient number, since it is larger than the sum of its proper divisors (10539687289).

20121221127 is an equidigital number, since it uses as much as digits as its factorization.

20121221127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 958153397.

The product of its (nonzero) digits is 224, while the sum is 21.

Adding to 20121221127 its reverse (72112212102), we get a palindrome (92233433229).

The spelling of 20121221127 in words is "twenty billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred twenty-seven".