21168450688 has 256 divisors, whose sum is σ = 55023206400. Its totient is φ = 7871385600.

The previous prime is 21168450647. The next prime is 21168450691. The reversal of 21168450688 is 88605486112.

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, 24136906 + ... + 24137782.

It is an arithmetic number, because the mean of its divisors is an integer number (214934400).

Almost surely, 2^21168450688 is an apocalyptic number.

21168450688 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 21168450688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27511603200).

21168450688 is an abundant number, since it is smaller than the sum of its proper divisors (33854755712).

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

21168450688 is a wasteful number, since it uses less digits than its factorization.

21168450688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019 (or 1007 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 49.

The spelling of 21168450688 in words is "twenty-one billion, one hundred sixty-eight million, four hundred fifty thousand, six hundred eighty-eight".