21014440123 has 4 divisors (see below), whose sum is σ = 21015526600. Its totient is φ = 21013353648.

The previous prime is 21014440121. The next prime is 21014440151. The reversal of 21014440123 is 32104441012.

It is a happy number.

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 21014440123 - 2¹ = 21014440121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21014440094 and 21014440103.

It is not an unprimeable number, because it can be changed into a prime (21014440121) 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, 513690 + ... + 553087.

It is an arithmetic number, because the mean of its divisors is an integer number (5253881650).

Almost surely, 2^21014440123 is an apocalyptic number.

21014440123 is a deficient number, since it is larger than the sum of its proper divisors (1086477).

21014440123 is a wasteful number, since it uses less digits than its factorization.

21014440123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086476.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21014440123 its reverse (32104441012), we get a palindrome (53118881135).

The spelling of 21014440123 in words is "twenty-one billion, fourteen million, four hundred forty thousand, one hundred twenty-three".