12021541878545 has 8 divisors (see below), whose sum is σ = 14505551085480. Its totient is φ = 9564099615360.

The previous prime is 12021541878497. The next prime is 12021541878553. The reversal of 12021541878545 is 54587814512021.

It can be written as a sum of positive squares in 4 ways, for example, as 539684175424 + 11481857703121 = 734632^2 + 3388489^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-12021541878545 is a prime.

It is a super-2 number, since 2×12021541878545² (a number of 27 digits) contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 6641734940 + ... + 6641736749.

It is an arithmetic number, because the mean of its divisors is an integer number (1813193885685).

Almost surely, 2^{12021541878545} is an apocalyptic number.

It is an amenable number.

12021541878545 is a deficient number, since it is larger than the sum of its proper divisors (2484009206935).

12021541878545 is a wasteful number, since it uses less digits than its factorization.

12021541878545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13283471875.

The product of its (nonzero) digits is 3584000, while the sum is 53.

The spelling of 12021541878545 in words is "twelve trillion, twenty-one billion, five hundred forty-one million, eight hundred seventy-eight thousand, five hundred forty-five".