12021541515205 has 4 divisors (see below), whose sum is σ = 14425849818252. Its totient is φ = 9617233212160.

The previous prime is 12021541515163. The next prime is 12021541515239. The reversal of 12021541515205 is 50251514512021.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2533798587681 + 9487742927524 = 1591791^2 + 3080218^2 .

It is not a de Polignac number, because 12021541515205 - 2¹⁵ = 12021541482437 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1202154151516 + ... + 1202154151525.

It is an arithmetic number, because the mean of its divisors is an integer number (3606462454563).

Almost surely, 2^{12021541515205} is an apocalyptic number.

It is an amenable number.

12021541515205 is a deficient number, since it is larger than the sum of its proper divisors (2404308303047).

12021541515205 is an equidigital number, since it uses as much as digits as its factorization.

12021541515205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2404308303046.

The product of its (nonzero) digits is 20000, while the sum is 34.

The spelling of 12021541515205 in words is "twelve trillion, twenty-one billion, five hundred forty-one million, five hundred fifteen thousand, two hundred five".