21488718050 has 18 divisors (see below), whose sum is σ = 39970943649. Its totient is φ = 8595072600.

The previous prime is 21488718037. The next prime is 21488718067. The reversal of 21488718050 is 5081788412.

It can be written as a sum of positive squares in 2 ways, for example, as 21058943689 + 429774361 = 145117^2 + 20731^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=103655.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21488717992 and 21488718010.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1026185 + ... + 1046915.

Almost surely, 2^21488718050 is an apocalyptic number.

21488718050 is a deficient number, since it is larger than the sum of its proper divisors (18482225599).

21488718050 is an frugal number, since it uses more digits than its factorization.

21488718050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41474 (or 20738 counting only the distinct ones).

The product of its (nonzero) digits is 143360, while the sum is 44.

The spelling of 21488718050 in words is "twenty-one billion, four hundred eighty-eight million, seven hundred eighteen thousand, fifty".