21643503036 has 24 divisors (see below), whose sum is σ = 50662862544. Its totient is φ = 7191450240.

The previous prime is 21643503031. The next prime is 21643503059. The reversal of 21643503036 is 63030534612.

It is a junction number, because it is equal to n+sod(n) for n = 21643502988 and 21643503006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21643503031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2877435 + ... + 2884946.

It is an arithmetic number, because the mean of its divisors is an integer number (2110952606).

Almost surely, 2^21643503036 is an apocalyptic number.

It is an amenable number.

21643503036 is an abundant number, since it is smaller than the sum of its proper divisors (29019359508).

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

21643503036 is a wasteful number, since it uses less digits than its factorization.

21643503036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5762701 (or 5762699 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 33.

The spelling of 21643503036 in words is "twenty-one billion, six hundred forty-three million, five hundred three thousand, thirty-six".