21404123304 has 32 divisors (see below), whose sum is σ = 53625909120. Its totient is φ = 7119294336.

The previous prime is 21404123281. The next prime is 21404123317. The reversal of 21404123304 is 40332140412.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 951997 + ... + 974220.

It is an arithmetic number, because the mean of its divisors is an integer number (1675809660).

Almost surely, 2^21404123304 is an apocalyptic number.

21404123304 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21404123304 is an abundant number, since it is smaller than the sum of its proper divisors (32221785816).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21404123304 is a wasteful number, since it uses less digits than its factorization.

21404123304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1926689 (or 1926685 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21404123304 its reverse (40332140412), we get a palindrome (61736263716).

The spelling of 21404123304 in words is "twenty-one billion, four hundred four million, one hundred twenty-three thousand, three hundred four".