21123310443203 has 16 divisors (see below), whose sum is σ = 21491241819840. Its totient is φ = 20757374668800.

The previous prime is 21123310443133. The next prime is 21123310443211. The reversal of 21123310443203 is 30234401332112.

It is a cyclic number.

It is not a de Polignac number, because 21123310443203 - 2¹⁴ = 21123310426819 is a prime.

It is a super-3 number, since 3×21123310443203³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21123310443283) 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, 75685373 + ... + 75963953.

It is an arithmetic number, because the mean of its divisors is an integer number (1343202613740).

Almost surely, 2^{21123310443203} is an apocalyptic number.

21123310443203 is a deficient number, since it is larger than the sum of its proper divisors (367931376637).

21123310443203 is a wasteful number, since it uses less digits than its factorization.

21123310443203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282158.

The product of its (nonzero) digits is 10368, while the sum is 29.

Adding to 21123310443203 its reverse (30234401332112), we get a palindrome (51357711775315).

The spelling of 21123310443203 in words is "twenty-one trillion, one hundred twenty-three billion, three hundred ten million, four hundred forty-three thousand, two hundred three".