21711020072 has 16 divisors (see below), whose sum is σ = 46523614560. Its totient is φ = 9304722864.

The previous prime is 21711020017. The next prime is 21711020083. The reversal of 21711020072 is 27002011712.

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 3 ways as a sum of consecutive naturals, for example, 193848338 + ... + 193848449.

It is an arithmetic number, because the mean of its divisors is an integer number (2907725910).

Almost surely, 2^21711020072 is an apocalyptic number.

It is an amenable number.

21711020072 is an abundant number, since it is smaller than the sum of its proper divisors (24812594488).

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

21711020072 is a wasteful number, since it uses less digits than its factorization.

21711020072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387696800 (or 387696796 counting only the distinct ones).

The product of its (nonzero) digits is 392, while the sum is 23.

Adding to 21711020072 its reverse (27002011712), we get a palindrome (48713031784).

The spelling of 21711020072 in words is "twenty-one billion, seven hundred eleven million, twenty thousand, seventy-two".