21404440123 has 8 divisors (see below), whose sum is σ = 23353802496. Its totient is φ = 19455661800.

The previous prime is 21404440073. The next prime is 21404440181. The reversal of 21404440123 is 32104440412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21404440123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21404440193) 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 7 ways as a sum of consecutive naturals, for example, 67543 + ... + 217648.

It is an arithmetic number, because the mean of its divisors is an integer number (2919225312).

Almost surely, 2^21404440123 is an apocalyptic number.

21404440123 is a deficient number, since it is larger than the sum of its proper divisors (1949362373).

21404440123 is a wasteful number, since it uses less digits than its factorization.

21404440123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292025.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21404440123 its reverse (32104440412), we get a palindrome (53508880535).

The spelling of 21404440123 in words is "twenty-one billion, four hundred four million, four hundred forty thousand, one hundred twenty-three".