21553120302 has 96 divisors (see below), whose sum is σ = 53482884768. Its totient is φ = 5753309184.

The previous prime is 21553120271. The next prime is 21553120327. The reversal of 21553120302 is 20302135512.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 668988 + ... + 700464.

It is an arithmetic number, because the mean of its divisors is an integer number (557113383).

Almost surely, 2^21553120302 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21553120302, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26741442384).

21553120302 is an abundant number, since it is smaller than the sum of its proper divisors (31929764466).

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

21553120302 is a wasteful number, since it uses less digits than its factorization.

21553120302 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31650 (or 31643 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

Adding to 21553120302 its reverse (20302135512), we get a palindrome (41855255814).

The spelling of 21553120302 in words is "twenty-one billion, five hundred fifty-three million, one hundred twenty thousand, three hundred two".