21011037936 has 160 divisors (see below), whose sum is σ = 65885925888. Its totient is φ = 5632450560.

The previous prime is 21011037907. The next prime is 21011037973. The reversal of 21011037936 is 63973011012.

It is a super-2 number, since 2×21011037936² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21011037897 and 21011037906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1885116 + ... + 1896228.

Almost surely, 2^21011037936 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 21011037936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32942962944).

21011037936 is an abundant number, since it is smaller than the sum of its proper divisors (44874887952).

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

21011037936 is a wasteful number, since it uses less digits than its factorization.

21011037936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11479 (or 11473 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 33.

Adding to 21011037936 its reverse (63973011012), we get a palindrome (84984048948).

The spelling of 21011037936 in words is "twenty-one billion, eleven million, thirty-seven thousand, nine hundred thirty-six".