21005524101 has 16 divisors (see below), whose sum is σ = 28069418048. Its totient is φ = 13972694400.

The previous prime is 21005524069. The next prime is 21005524159. The reversal of 21005524101 is 10142550012.

It is not a de Polignac number, because 21005524101 - 2⁵ = 21005524069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21005524201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2774361 + ... + 2781921.

It is an arithmetic number, because the mean of its divisors is an integer number (1754338628).

Almost surely, 2^21005524101 is an apocalyptic number.

It is an amenable number.

21005524101 is a deficient number, since it is larger than the sum of its proper divisors (7063893947).

21005524101 is a wasteful number, since it uses less digits than its factorization.

21005524101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9492.

The product of its (nonzero) digits is 400, while the sum is 21.

The spelling of 21005524101 in words is "twenty-one billion, five million, five hundred twenty-four thousand, one hundred one".