21555368159019 has 16 divisors (see below), whose sum is σ = 30303654432000. Its totient is φ = 13591188969696.

The previous prime is 21555368158967. The next prime is 21555368159041. The reversal of 21555368159019 is 91095186355512.

It is not a de Polignac number, because 21555368159019 - 2⁹ = 21555368158507 is a prime.

It is a super-2 number, since 2×21555368159019² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21555368159089) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 315628924 + ... + 315697209.

It is an arithmetic number, because the mean of its divisors is an integer number (1893978402000).

Almost surely, 2^{21555368159019} is an apocalyptic number.

21555368159019 is a deficient number, since it is larger than the sum of its proper divisors (8748286272981).

21555368159019 is a wasteful number, since it uses less digits than its factorization.

21555368159019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 631326754.

The product of its (nonzero) digits is 14580000, while the sum is 60.

The spelling of 21555368159019 in words is "twenty-one trillion, five hundred fifty-five billion, three hundred sixty-eight million, one hundred fifty-nine thousand, nineteen".