21038870016 has 180 divisors, whose sum is σ = 63061836552. Its totient is φ = 7011836928.

The previous prime is 21038869931. The next prime is 21038870077. The reversal of 21038870016 is 61007883012.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 3356101 + ... + 3362363.

Almost surely, 2^21038870016 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21038870016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31530918276).

21038870016 is an abundant number, since it is smaller than the sum of its proper divisors (42022966536).

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

21038870016 is an frugal number, since it uses more digits than its factorization.

21038870016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6305 (or 6268 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 21038870016 in words is "twenty-one billion, thirty-eight million, eight hundred seventy thousand, sixteen".