21404104050 has 144 divisors (see below), whose sum is σ = 62297521632. Its totient is φ = 4848883200.

The previous prime is 21404104049. The next prime is 21404104081. The reversal of 21404104050 is 5040140412.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 817665 + ... + 843435.

It is an arithmetic number, because the mean of its divisors is an integer number (432621678).

Almost surely, 2^21404104050 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21404104050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31148760816).

21404104050 is an abundant number, since it is smaller than the sum of its proper divisors (40893417582).

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

21404104050 is a wasteful number, since it uses less digits than its factorization.

21404104050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25913 (or 25901 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

Adding to 21404104050 its reverse (5040140412), we get a palindrome (26444244462).

The spelling of 21404104050 in words is "twenty-one billion, four hundred four million, one hundred four thousand, fifty".