21126186452 has 48 divisors (see below), whose sum is σ = 43953840000. Its totient is φ = 8692973184.

The previous prime is 21126186439. The next prime is 21126186457. The reversal of 21126186452 is 25468162112.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21126186457) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72674 + ... + 218022.

It is an arithmetic number, because the mean of its divisors is an integer number (915705000).

Almost surely, 2^21126186452 is an apocalyptic number.

It is a pronic number, being equal to 145348×145349.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21126186452, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21976920000).

21126186452 is an abundant number, since it is smaller than the sum of its proper divisors (22827653548).

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

21126186452 is a wasteful number, since it uses less digits than its factorization.

21126186452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145568 (or 145566 counting only the distinct ones).

The product of its digits is 46080, while the sum is 38.

The spelling of 21126186452 in words is "twenty-one billion, one hundred twenty-six million, one hundred eighty-six thousand, four hundred fifty-two".