13105401515621 has 2 divisors, whose sum is σ = 13105401515622. Its totient is φ = 13105401515620.

The previous prime is 13105401515537. The next prime is 13105401515629. The reversal of 13105401515621 is 12651510450131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11937294491521 + 1168107024100 = 3455039^2 + 1080790^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13105401515621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13105401515629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6552700757810 + 6552700757811.

It is an arithmetic number, because the mean of its divisors is an integer number (6552700757811).

Almost surely, 2^{13105401515621} is an apocalyptic number.

It is an amenable number.

13105401515621 is a deficient number, since it is larger than the sum of its proper divisors (1).

13105401515621 is an equidigital number, since it uses as much as digits as its factorization.

13105401515621 is an evil number, because the sum of its binary digits is even.

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

Adding to 13105401515621 its reverse (12651510450131), we get a palindrome (25756911965752).

The spelling of 13105401515621 in words is "thirteen trillion, one hundred five billion, four hundred one million, five hundred fifteen thousand, six hundred twenty-one".