21936505784 has 48 divisors (see below), whose sum is σ = 43752211200. Its totient is φ = 10308985344.

The previous prime is 21936505753. The next prime is 21936505837. The reversal of 21936505784 is 48750563912.

It is a happy number.

It is a super-2 number, since 2×21936505784² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 336872 + ... + 396680.

It is an arithmetic number, because the mean of its divisors is an integer number (911504400).

It is a 1-persistent number, because it is pandigital, but 2⋅21936505784 = 43873011568 is not.

Almost surely, 2^21936505784 is an apocalyptic number.

It is an amenable number.

21936505784 is a deficient number, since it is larger than the sum of its proper divisors (21815705416).

21936505784 is a wasteful number, since it uses less digits than its factorization.

21936505784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59980 (or 59957 counting only the distinct ones).

The product of its (nonzero) digits is 1814400, while the sum is 50.

The spelling of 21936505784 in words is "twenty-one billion, nine hundred thirty-six million, five hundred five thousand, seven hundred eighty-four".