21201053405 has 16 divisors (see below), whose sum is σ = 29084824704. Its totient is φ = 14533318080.

The previous prime is 21201053369. The next prime is 21201053407. The reversal of 21201053405 is 50435010212.

It is not a de Polignac number, because 21201053405 - 2¹⁰ = 21201052381 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201053407) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 20750 + ... + 206960.

It is an arithmetic number, because the mean of its divisors is an integer number (1817801544).

Almost surely, 2^21201053405 is an apocalyptic number.

It is an amenable number.

21201053405 is a deficient number, since it is larger than the sum of its proper divisors (7883771299).

21201053405 is a wasteful number, since it uses less digits than its factorization.

21201053405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189476.

The product of its (nonzero) digits is 1200, while the sum is 23.

Adding to 21201053405 its reverse (50435010212), we get a palindrome (71636063617).

The spelling of 21201053405 in words is "twenty-one billion, two hundred one million, fifty-three thousand, four hundred five".