21020668319028 has 96 divisors (see below), whose sum is σ = 56187183596544. Its totient is φ = 5991766679808.

The previous prime is 21020668318967. The next prime is 21020668319033. The reversal of 21020668319028 is 82091386602012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87778951 + ... + 88018097.

It is an arithmetic number, because the mean of its divisors is an integer number (585283162464).

Almost surely, 2^{21020668319028} is an apocalyptic number.

21020668319028 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21020668319028 is an abundant number, since it is smaller than the sum of its proper divisors (35166515277516).

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

21020668319028 is a wasteful number, since it uses less digits than its factorization.

21020668319028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241621 (or 241619 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 48.

The spelling of 21020668319028 in words is "twenty-one trillion, twenty billion, six hundred sixty-eight million, three hundred nineteen thousand, twenty-eight".