21113525461361 has 2 divisors, whose sum is σ = 21113525461362. Its totient is φ = 21113525461360.

The previous prime is 21113525461351. The next prime is 21113525461367. The reversal of 21113525461361 is 16316452531112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19424645875600 + 1688879585761 = 4407340^2 + 1299569^2 .

It is a cyclic number.

It is not a de Polignac number, because 21113525461361 - 2³⁰ = 21112451719537 is a prime.

It is not a weakly prime, because it can be changed into another prime (21113525461367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556762730680 + 10556762730681.

It is an arithmetic number, because the mean of its divisors is an integer number (10556762730681).

Almost surely, 2^{21113525461361} is an apocalyptic number.

It is an amenable number.

21113525461361 is a deficient number, since it is larger than the sum of its proper divisors (1).

21113525461361 is an equidigital number, since it uses as much as digits as its factorization.

21113525461361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 41.

Adding to 21113525461361 its reverse (16316452531112), we get a palindrome (37429977992473).

The spelling of 21113525461361 in words is "twenty-one trillion, one hundred thirteen billion, five hundred twenty-five million, four hundred sixty-one thousand, three hundred sixty-one".