21031653888 has 960 divisors, whose sum is σ = 80074874880. Its totient is φ = 5374771200.

The previous prime is 21031653883. The next prime is 21031653901. The reversal of 21031653888 is 88835613012.

21031653888 is a `hidden beast` number, since 2 + 1 + 0 + 31 + 6 + 538 + 88 = 666.

It is not an unprimeable number, because it can be changed into a prime (21031653883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 512967148 + ... + 512967188.

It is an arithmetic number, because the mean of its divisors is an integer number (83411328).

Almost surely, 2^21031653888 is an apocalyptic number.

21031653888 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 21031653888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40037437440).

21031653888 is an abundant number, since it is smaller than the sum of its proper divisors (59043220992).

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

21031653888 is an equidigital number, since it uses as much as digits as its factorization.

21031653888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 21031653888 in words is "twenty-one billion, thirty-one million, six hundred fifty-three thousand, eight hundred eighty-eight".