21038715672 has 128 divisors (see below), whose sum is σ = 57435322560. Its totient is φ = 6383370240.

The previous prime is 21038715671. The next prime is 21038715727. The reversal of 21038715672 is 27651783012.

It is a super-3 number, since 3×21038715672³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21038715671) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 9471522 + ... + 9473742.

Almost surely, 2^21038715672 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 21038715672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28717661280).

21038715672 is an abundant number, since it is smaller than the sum of its proper divisors (36396606888).

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

21038715672 is a wasteful number, since it uses less digits than its factorization.

21038715672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2653 (or 2649 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 42.

The spelling of 21038715672 in words is "twenty-one billion, thirty-eight million, seven hundred fifteen thousand, six hundred seventy-two".