21021020210228 has 12 divisors (see below), whose sum is σ = 36854783126532. Its totient is φ = 10491082174080.

The previous prime is 21021020210227. The next prime is 21021020210257. The reversal of 21021020210228 is 82201202012012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4659545325604 + 16361474884624 = 2158598^2 + 4044932^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021020210221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4856980325 + ... + 4856984652.

It is an arithmetic number, because the mean of its divisors is an integer number (3071231927211).

Almost surely, 2^{21021020210228} is an apocalyptic number.

It is an amenable number.

21021020210228 is a deficient number, since it is larger than the sum of its proper divisors (15833762916304).

21021020210228 is a wasteful number, since it uses less digits than its factorization.

21021020210228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9713965522 (or 9713965520 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 23.

The spelling of 21021020210228 in words is "twenty-one trillion, twenty-one billion, twenty million, two hundred ten thousand, two hundred twenty-eight".