20121221139 has 8 divisors (see below), whose sum is σ = 26828952000. Its totient is φ = 13413818856.

The previous prime is 20121221137. The next prime is 20121221161. The reversal of 20121221139 is 93112212102.

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

It is not a de Polignac number, because 20121221139 - 2¹ = 20121221137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20121221137) 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, 183112 + ... + 271610.

It is an arithmetic number, because the mean of its divisors is an integer number (3353619000).

Almost surely, 2^20121221139 is an apocalyptic number.

20121221139 is a deficient number, since it is larger than the sum of its proper divisors (6707730861).

20121221139 is an equidigital number, since it uses as much as digits as its factorization.

20121221139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164289.

The product of its (nonzero) digits is 432, while the sum is 24.

The spelling of 20121221139 in words is "twenty billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred thirty-nine".