21308011452 has 216 divisors, whose sum is σ = 66857132160. Its totient is φ = 5602746240.

The previous prime is 21308011421. The next prime is 21308011457. The reversal of 21308011452 is 25411080312.

21308011452 is a `hidden beast` number, since 2 + 130 + 80 + 1 + 1 + 452 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21308011457) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 20910199 + ... + 20911217.

It is an arithmetic number, because the mean of its divisors is an integer number (309523760).

Almost surely, 2^21308011452 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 21308011452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33428566080).

21308011452 is an abundant number, since it is smaller than the sum of its proper divisors (45549120708).

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

21308011452 is a wasteful number, since it uses less digits than its factorization.

21308011452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1553 (or 1535 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

Adding to 21308011452 its reverse (25411080312), we get a palindrome (46719091764).

The spelling of 21308011452 in words is "twenty-one billion, three hundred eight million, eleven thousand, four hundred fifty-two".