21088327428 has 96 divisors (see below), whose sum is σ = 62537529600. Its totient is φ = 6020068608.

The previous prime is 21088327427. The next prime is 21088327439. The reversal of 21088327428 is 82472388012.

21088327428 is a `hidden beast` number, since 210 + 8 + 8 + 3 + 2 + 7 + 428 = 666.

It is not an unprimeable number, because it can be changed into a prime (21088327427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 917776 + ... + 940472.

It is an arithmetic number, because the mean of its divisors is an integer number (651432600).

Almost surely, 2^21088327428 is an apocalyptic number.

21088327428 is a gapful number since it is divisible by the number (28) 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 21088327428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31268764800).

21088327428 is an abundant number, since it is smaller than the sum of its proper divisors (41449202172).

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

21088327428 is a wasteful number, since it uses less digits than its factorization.

21088327428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23946 (or 23938 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 45.

The spelling of 21088327428 in words is "twenty-one billion, eighty-eight million, three hundred twenty-seven thousand, four hundred twenty-eight".