21039817216 has 40 divisors (see below), whose sum is σ = 45860238864. Its totient is φ = 9563550720.

The previous prime is 21039817207. The next prime is 21039817217. The reversal of 21039817216 is 61271893012.

It is not an unprimeable number, because it can be changed into a prime (21039817217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1862250 + ... + 1873513.

Almost surely, 2^21039817216 is an apocalyptic number.

It is an amenable number.

21039817216 is an abundant number, since it is smaller than the sum of its proper divisors (24820421648).

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

21039817216 is an equidigital number, since it uses as much as digits as its factorization.

21039817216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3735792 (or 3735776 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 21039817216 in words is "twenty-one billion, thirty-nine million, eight hundred seventeen thousand, two hundred sixteen".