21646201353 has 16 divisors (see below), whose sum is σ = 33876167040. Its totient is φ = 12034953216.

The previous prime is 21646201349. The next prime is 21646201361. The reversal of 21646201353 is 35310264612.

It is not a de Polignac number, because 21646201353 - 2² = 21646201349 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21646201363) 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, 13928568 + ... + 13930121.

It is an arithmetic number, because the mean of its divisors is an integer number (2117260440).

Almost surely, 2^21646201353 is an apocalyptic number.

It is an amenable number.

21646201353 is a deficient number, since it is larger than the sum of its proper divisors (12229965687).

21646201353 is a wasteful number, since it uses less digits than its factorization.

21646201353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27858736.

The product of its (nonzero) digits is 25920, while the sum is 33.

Adding to 21646201353 its reverse (35310264612), we get a palindrome (56956465965).

The spelling of 21646201353 in words is "twenty-one billion, six hundred forty-six million, two hundred one thousand, three hundred fifty-three".