20121212005 has 8 divisors (see below), whose sum is σ = 24924340224. Its totient is φ = 15577712400.

The previous prime is 20121211967. The next prime is 20121212011. The reversal of 20121212005 is 50021212102.

It is a happy number.

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

It is not a de Polignac number, because 20121212005 - 2¹⁵ = 20121179237 is a prime.

It is a super-2 number, since 2×20121212005² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20121212005.

It is a congruent number.

It is an unprimeable number.

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, 64906981 + ... + 64907290.

It is an arithmetic number, because the mean of its divisors is an integer number (3115542528).

Almost surely, 2^20121212005 is an apocalyptic number.

It is an amenable number.

20121212005 is a deficient number, since it is larger than the sum of its proper divisors (4803128219).

20121212005 is a wasteful number, since it uses less digits than its factorization.

20121212005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129814307.

The product of its (nonzero) digits is 80, while the sum is 16.

Adding to 20121212005 its reverse (50021212102), we get a palindrome (70142424107).

The spelling of 20121212005 in words is "twenty billion, one hundred twenty-one million, two hundred twelve thousand, five".