21545552305013 has 16 divisors (see below), whose sum is σ = 23512240680192. Its totient is φ = 19580198664000.

The previous prime is 21545552305001. The next prime is 21545552305027. The reversal of 21545552305013 is 31050325554512.

It is a cyclic number.

It is not a de Polignac number, because 21545552305013 - 2¹⁸ = 21545552042869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21545552305063) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 547614020 + ... + 547653362.

It is an arithmetic number, because the mean of its divisors is an integer number (1469515042512).

Almost surely, 2^{21545552305013} is an apocalyptic number.

It is an amenable number.

21545552305013 is a deficient number, since it is larger than the sum of its proper divisors (1966688375179).

21545552305013 is a wasteful number, since it uses less digits than its factorization.

21545552305013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55036.

The product of its (nonzero) digits is 450000, while the sum is 41.

Adding to 21545552305013 its reverse (31050325554512), we get a palindrome (52595877859525).

The spelling of 21545552305013 in words is "twenty-one trillion, five hundred forty-five billion, five hundred fifty-two million, three hundred five thousand, thirteen".