21355223056243 has 8 divisors (see below), whose sum is σ = 21407020614000. Its totient is φ = 21303430582560.

The previous prime is 21355223056229. The next prime is 21355223056261. The reversal of 21355223056243 is 34265032255312.

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

It is a cyclic number.

It is not a de Polignac number, because 21355223056243 - 2¹³ = 21355223048051 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21355223056243.

It is not an unprimeable number, because it can be changed into a prime (21355223056213) 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 7 ways as a sum of consecutive naturals, for example, 7208508 + ... + 9730006.

It is an arithmetic number, because the mean of its divisors is an integer number (2675877576750).

Almost surely, 2^{21355223056243} is an apocalyptic number.

21355223056243 is a deficient number, since it is larger than the sum of its proper divisors (51797557757).

21355223056243 is a wasteful number, since it uses less digits than its factorization.

21355223056243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2542037.

The product of its (nonzero) digits is 1296000, while the sum is 43.

The spelling of 21355223056243 in words is "twenty-one trillion, three hundred fifty-five billion, two hundred twenty-three million, fifty-six thousand, two hundred forty-three".