21155211311453 has 16 divisors (see below), whose sum is σ = 22715737513920. Its totient is φ = 19642431384576.

The previous prime is 21155211311441. The next prime is 21155211311477. The reversal of 21155211311453 is 35411311255112.

It is a cyclic number.

It is not a de Polignac number, because 21155211311453 - 2⁶ = 21155211311389 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 (21155211314453) 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, 41927876 + ... + 42429437.

It is an arithmetic number, because the mean of its divisors is an integer number (1419733594620).

Almost surely, 2^{21155211311453} is an apocalyptic number.

It is an amenable number.

21155211311453 is a deficient number, since it is larger than the sum of its proper divisors (1560526202467).

21155211311453 is a wasteful number, since it uses less digits than its factorization.

21155211311453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84357596.

The product of its digits is 18000, while the sum is 35.

Adding to 21155211311453 its reverse (35411311255112), we get a palindrome (56566522566565).

The spelling of 21155211311453 in words is "twenty-one trillion, one hundred fifty-five billion, two hundred eleven million, three hundred eleven thousand, four hundred fifty-three".