21126532320 has 192 divisors, whose sum is σ = 75941893440. Its totient is φ = 5481437184.

The previous prime is 21126532279. The next prime is 21126532337. The reversal of 21126532320 is 2323562112.

It is a happy number.

21126532320 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 653 + 2 + 3 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93754 + ... + 225926.

It is an arithmetic number, because the mean of its divisors is an integer number (395530695).

Almost surely, 2^21126532320 is an apocalyptic number.

21126532320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21126532320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37970946720).

21126532320 is an abundant number, since it is smaller than the sum of its proper divisors (54815361120).

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

21126532320 is a wasteful number, since it uses less digits than its factorization.

21126532320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132234 (or 132220 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The spelling of 21126532320 in words is "twenty-one billion, one hundred twenty-six million, five hundred thirty-two thousand, three hundred twenty".