21404440104 has 32 divisors (see below), whose sum is σ = 56658813120. Its totient is φ = 6715118336.

The previous prime is 21404440073. The next prime is 21404440181. The reversal of 21404440104 is 40104440412.

It is a happy number.

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, 26230524 + ... + 26231339.

It is an arithmetic number, because the mean of its divisors is an integer number (1770587910).

Almost surely, 2^21404440104 is an apocalyptic number.

21404440104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21404440104 is an abundant number, since it is smaller than the sum of its proper divisors (35254373016).

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

21404440104 is a wasteful number, since it uses less digits than its factorization.

21404440104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52461889 (or 52461885 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 24.

Adding to 21404440104 its reverse (40104440412), we get a palindrome (61508880516).

The spelling of 21404440104 in words is "twenty-one billion, four hundred four million, four hundred forty thousand, one hundred four".