21530354420204 has 96 divisors (see below), whose sum is σ = 43985739764736. Its totient is φ = 9029983322880.

The previous prime is 21530354420173. The next prime is 21530354420209. The reversal of 21530354420204 is 40202445303512.

It is a happy number.

It is a super-2 number, since 2×21530354420204² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21530354420209) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2412900887 + ... + 2412909809.

It is an arithmetic number, because the mean of its divisors is an integer number (458184789216).

Almost surely, 2^{21530354420204} 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 21530354420204, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21992869882368).

21530354420204 is an abundant number, since it is smaller than the sum of its proper divisors (22455385344532).

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

21530354420204 is a wasteful number, since it uses less digits than its factorization.

21530354420204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12975 (or 12973 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 35.

Adding to 21530354420204 its reverse (40202445303512), we get a palindrome (61732799723716).

The spelling of 21530354420204 in words is "twenty-one trillion, five hundred thirty billion, three hundred fifty-four million, four hundred twenty thousand, two hundred four".