21104855523 has 6 divisors (see below), whose sum is σ = 30484791324. Its totient is φ = 14069903676.

The previous prime is 21104855503. The next prime is 21104855539. The reversal of 21104855523 is 32555840112.

21104855523 is a `hidden beast` number, since 21 + 1 + 0 + 4 + 85 + 552 + 3 = 666.

It is not a de Polignac number, because 21104855523 - 2⁵ = 21104855491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21104855503) by changing a digit.

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 in 5 ways as a sum of consecutive naturals, for example, 1172491965 + ... + 1172491982.

It is an arithmetic number, because the mean of its divisors is an integer number (5080798554).

Almost surely, 2^21104855523 is an apocalyptic number.

21104855523 is a deficient number, since it is larger than the sum of its proper divisors (9379935801).

21104855523 is a wasteful number, since it uses less digits than its factorization.

21104855523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2344983953 (or 2344983950 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The spelling of 21104855523 in words is "twenty-one billion, one hundred four million, eight hundred fifty-five thousand, five hundred twenty-three".