21616216513405 has 16 divisors (see below), whose sum is σ = 26643804110784. Its totient is φ = 16829629724160.

The previous prime is 21616216513391. The next prime is 21616216513421. The reversal of 21616216513405 is 50431561261612.

It is not a de Polignac number, because 21616216513405 - 2⁷ = 21616216513277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 388683156 + ... + 388738765.

It is an arithmetic number, because the mean of its divisors is an integer number (1665237756924).

Almost surely, 2^{21616216513405} is an apocalyptic number.

It is an amenable number.

21616216513405 is a deficient number, since it is larger than the sum of its proper divisors (5027587597379).

21616216513405 is an equidigital number, since it uses as much as digits as its factorization.

21616216513405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 777422076.

The product of its (nonzero) digits is 259200, while the sum is 43.

The spelling of 21616216513405 in words is "twenty-one trillion, six hundred sixteen billion, two hundred sixteen million, five hundred thirteen thousand, four hundred five".