21243928028 has 6 divisors (see below), whose sum is σ = 37176874056. Its totient is φ = 10621964012.

The previous prime is 21243927997. The next prime is 21243928091. The reversal of 21243928028 is 82082934212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2655491000 + ... + 2655491007.

It is an arithmetic number, because the mean of its divisors is an integer number (6196145676).

Almost surely, 2^21243928028 is an apocalyptic number.

It is an amenable number.

21243928028 is a deficient number, since it is larger than the sum of its proper divisors (15932946028).

21243928028 is a wasteful number, since it uses less digits than its factorization.

21243928028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5310982011 (or 5310982009 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 41.

The spelling of 21243928028 in words is "twenty-one billion, two hundred forty-three million, nine hundred twenty-eight thousand, twenty-eight".