21736509436 has 48 divisors (see below), whose sum is σ = 39558800736. Its totient is φ = 10442041344.

The previous prime is 21736509401. The next prime is 21736509439. The reversal of 21736509436 is 63490563712.

It is a super-2 number, since 2×21736509436² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21736509439) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5334696 + ... + 5338768.

It is an arithmetic number, because the mean of its divisors is an integer number (824141682).

Almost surely, 2^21736509436 is an apocalyptic number.

It is an amenable number.

21736509436 is a deficient number, since it is larger than the sum of its proper divisors (17822291300).

21736509436 is a wasteful number, since it uses less digits than its factorization.

21736509436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4558 (or 4556 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 46.

The spelling of 21736509436 in words is "twenty-one billion, seven hundred thirty-six million, five hundred nine thousand, four hundred thirty-six".