21373534355505 has 16 divisors (see below), whose sum is σ = 34289337698880. Its totient is φ = 11368657412928.

The previous prime is 21373534355501. The next prime is 21373534355507. The reversal of 21373534355505 is 50555343537312.

It is not a de Polignac number, because 21373534355505 - 2² = 21373534355501 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21373534355501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1910051095 + ... + 1910062284.

It is an arithmetic number, because the mean of its divisors is an integer number (2143083606180).

Almost surely, 2^{21373534355505} is an apocalyptic number.

It is an amenable number.

21373534355505 is a deficient number, since it is larger than the sum of its proper divisors (12915803343375).

21373534355505 is a wasteful number, since it uses less digits than its factorization.

21373534355505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3820113760.

The product of its (nonzero) digits is 14175000, while the sum is 51.

The spelling of 21373534355505 in words is "twenty-one trillion, three hundred seventy-three billion, five hundred thirty-four million, three hundred fifty-five thousand, five hundred five".