21256433036 has 12 divisors (see below), whose sum is σ = 38063845512. Its totient is φ = 10381048608.

The previous prime is 21256432979. The next prime is 21256433069. The reversal of 21256433036 is 63033465212.

It is a junction number, because it is equal to n+sod(n) for n = 21256432987 and 21256433005.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61791785 + ... + 61792128.

It is an arithmetic number, because the mean of its divisors is an integer number (3171987126).

Almost surely, 2^21256433036 is an apocalyptic number.

It is an amenable number.

21256433036 is a deficient number, since it is larger than the sum of its proper divisors (16807412476).

21256433036 is a wasteful number, since it uses less digits than its factorization.

21256433036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123583960 (or 123583958 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 35.

Adding to 21256433036 its reverse (63033465212), we get a palindrome (84289898248).

The spelling of 21256433036 in words is "twenty-one billion, two hundred fifty-six million, four hundred thirty-three thousand, thirty-six".