21450611105513 has 2 divisors, whose sum is σ = 21450611105514. Its totient is φ = 21450611105512.

The previous prime is 21450611105467. The next prime is 21450611105621. The reversal of 21450611105513 is 31550111605412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13910490524329 + 7540120581184 = 3729677^2 + 2745928^2 .

It is a cyclic number.

It is not a de Polignac number, because 21450611105513 - 2⁸ = 21450611105257 is a prime.

It is not a weakly prime, because it can be changed into another prime (21450611105113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10725305552756 + 10725305552757.

It is an arithmetic number, because the mean of its divisors is an integer number (10725305552757).

Almost surely, 2^{21450611105513} is an apocalyptic number.

It is an amenable number.

21450611105513 is a deficient number, since it is larger than the sum of its proper divisors (1).

21450611105513 is an equidigital number, since it uses as much as digits as its factorization.

21450611105513 is an odious number, because the sum of its binary digits is odd.

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

The spelling of 21450611105513 in words is "twenty-one trillion, four hundred fifty billion, six hundred eleven million, one hundred five thousand, five hundred thirteen".