21312021302028 has 72 divisors (see below), whose sum is σ = 57059897141520. Its totient is φ = 6683909068800.

The previous prime is 21312021302027. The next prime is 21312021302063. The reversal of 21312021302028 is 82020312021312.

21312021302028 is a `hidden beast` number, since 2 + 1 + 312 + 0 + 21 + 302 + 0 + 28 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 21312021301992 and 21312021302010.

It is not an unprimeable number, because it can be changed into a prime (21312021302027) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3919773 + ... + 7615028.

It is an arithmetic number, because the mean of its divisors is an integer number (792498571410).

Almost surely, 2^{21312021302028} is an apocalyptic number.

It is an amenable number.

21312021302028 is an abundant number, since it is smaller than the sum of its proper divisors (35747875839492).

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

21312021302028 is a wasteful number, since it uses less digits than its factorization.

21312021302028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11537847 (or 11537842 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The spelling of 21312021302028 in words is "twenty-one trillion, three hundred twelve billion, twenty-one million, three hundred two thousand, twenty-eight".