21404320023 has 8 divisors (see below), whose sum is σ = 28546632688. Its totient is φ = 14265777024.

The previous prime is 21404320019. The next prime is 21404320039. The reversal of 21404320023 is 32002340412.

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

It is not a de Polignac number, because 21404320023 - 2² = 21404320019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404320823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 929140 + ... + 951897.

It is an arithmetic number, because the mean of its divisors is an integer number (3568329086).

Almost surely, 2^21404320023 is an apocalyptic number.

21404320023 is a deficient number, since it is larger than the sum of its proper divisors (7142312665).

21404320023 is a wasteful number, since it uses less digits than its factorization.

21404320023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1884833.

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 21404320023 its reverse (32002340412), we get a palindrome (53406660435).

The spelling of 21404320023 in words is "twenty-one billion, four hundred four million, three hundred twenty thousand, twenty-three".