21321235453 has 16 divisors (see below), whose sum is σ = 26275213440. Its totient is φ = 16891200000.

The previous prime is 21321235409. The next prime is 21321235469. The reversal of 21321235453 is 35453212312.

It is a cyclic number.

It is not a de Polignac number, because 21321235453 - 2¹³ = 21321227261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21321235553) 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, 1949548 + ... + 1960453.

It is an arithmetic number, because the mean of its divisors is an integer number (1642200840).

Almost surely, 2^21321235453 is an apocalyptic number.

It is an amenable number.

21321235453 is a deficient number, since it is larger than the sum of its proper divisors (4953977987).

21321235453 is a wasteful number, since it uses less digits than its factorization.

21321235453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3910068.

The product of its digits is 21600, while the sum is 31.

Adding to 21321235453 its reverse (35453212312), we get a palindrome (56774447765).

The spelling of 21321235453 in words is "twenty-one billion, three hundred twenty-one million, two hundred thirty-five thousand, four hundred fifty-three".