21404402364 has 72 divisors (see below), whose sum is σ = 53846719360. Its totient is φ = 6614809344.

The previous prime is 21404402363. The next prime is 21404402377. The reversal of 21404402364 is 46320440412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21404402363) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 186297 + ... + 278415.

Almost surely, 2^21404402364 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21404402364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26923359680).

21404402364 is an abundant number, since it is smaller than the sum of its proper divisors (32442316996).

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

21404402364 is a wasteful number, since it uses less digits than its factorization.

21404402364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92227 (or 92208 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 30.

Adding to 21404402364 its reverse (46320440412), we get a palindrome (67724842776).

The spelling of 21404402364 in words is "twenty-one billion, four hundred four million, four hundred two thousand, three hundred sixty-four".