21135445333131 has 32 divisors (see below), whose sum is σ = 28511075755008. Its totient is φ = 13926198850560.

The previous prime is 21135445333117. The next prime is 21135445333169. The reversal of 21135445333131 is 13133354453112.

It is not a de Polignac number, because 21135445333131 - 2¹⁰ = 21135445332107 is a prime.

It is a super-2 number, since 2×21135445333131² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21135445333131.

It is not an unprimeable number, because it can be changed into a prime (21135445333231) 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 31 ways as a sum of consecutive naturals, for example, 77984151 + ... + 78254703.

It is an arithmetic number, because the mean of its divisors is an integer number (890971117344).

Almost surely, 2^{21135445333131} is an apocalyptic number.

21135445333131 is a deficient number, since it is larger than the sum of its proper divisors (7375630421877).

21135445333131 is a wasteful number, since it uses less digits than its factorization.

21135445333131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271611.

The product of its digits is 194400, while the sum is 39.

Adding to 21135445333131 its reverse (13133354453112), we get a palindrome (34268799786243).

The spelling of 21135445333131 in words is "twenty-one trillion, one hundred thirty-five billion, four hundred forty-five million, three hundred thirty-three thousand, one hundred thirty-one".