21050042500423 has 4 divisors (see below), whose sum is σ = 21618962568040. Its totient is φ = 20481122432808.

The previous prime is 21050042500411. The next prime is 21050042500439. The reversal of 21050042500423 is 32400524005012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21050042500423 - 2¹³ = 21050042492231 is a prime.

It is a super-2 number, since 2×21050042500423² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21050042500391 and 21050042500400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21050042509423) 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 3 ways as a sum of consecutive naturals, for example, 284460033753 + ... + 284460033826.

It is an arithmetic number, because the mean of its divisors is an integer number (5404740642010).

Almost surely, 2^{21050042500423} is an apocalyptic number.

21050042500423 is a deficient number, since it is larger than the sum of its proper divisors (568920067617).

21050042500423 is an equidigital number, since it uses as much as digits as its factorization.

21050042500423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 568920067616.

The product of its (nonzero) digits is 9600, while the sum is 28.

Adding to 21050042500423 its reverse (32400524005012), we get a palindrome (53450566505435).

The spelling of 21050042500423 in words is "twenty-one trillion, fifty billion, forty-two million, five hundred thousand, four hundred twenty-three".