21103343009991 has 72 divisors (see below), whose sum is σ = 34308486692480. Its totient is φ = 12483862443360.

The previous prime is 21103343009941. The next prime is 21103343010031. The reversal of 21103343009991 is 19990034330112.

It is a happy number.

21103343009991 is a `hidden beast` number, since 2 + 1 + 1 + 0 + 334 + 300 + 9 + 9 + 9 + 1 = 666.

It is not a de Polignac number, because 21103343009991 - 2⁹ = 21103343009479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103343009941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 68166150 + ... + 68475036.

Almost surely, 2^{21103343009991} is an apocalyptic number.

21103343009991 is a deficient number, since it is larger than the sum of its proper divisors (13205143682489).

21103343009991 is a wasteful number, since it uses less digits than its factorization.

21103343009991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 310417 (or 310403 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 45.

The spelling of 21103343009991 in words is "twenty-one trillion, one hundred three billion, three hundred forty-three million, nine thousand, nine hundred ninety-one".