21200018652968 has 8 divisors (see below), whose sum is σ = 39750034974330. Its totient is φ = 10600009326480.

The previous prime is 21200018652949. The next prime is 21200018652977. The reversal of 21200018652968 is 86925681000212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17920811956804 + 3279206696164 = 4233298^2 + 1810858^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21200018652968² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1325001165803 + ... + 1325001165818.

Almost surely, 2^{21200018652968} is an apocalyptic number.

It is an amenable number.

21200018652968 is a deficient number, since it is larger than the sum of its proper divisors (18550016321362).

21200018652968 is a wasteful number, since it uses less digits than its factorization.

21200018652968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2650002331627 (or 2650002331623 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 50.

The spelling of 21200018652968 in words is "twenty-one trillion, two hundred billion, eighteen million, six hundred fifty-two thousand, nine hundred sixty-eight".