216172018853657 has 2 divisors, whose sum is σ = 216172018853658. Its totient is φ = 216172018853656.

The previous prime is 216172018853641. The next prime is 216172018853699. The reversal of 216172018853657 is 756358810271612.

It is a happy number.

216172018853657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138050656254016 + 78121362599641 = 11749496^2 + 8838629^2 .

It is a cyclic number.

It is not a de Polignac number, because 216172018853657 - 2⁴ = 216172018853641 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216172018853657.

It is not a weakly prime, because it can be changed into another prime (216172018850657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108086009426828 + 108086009426829.

It is an arithmetic number, because the mean of its divisors is an integer number (108086009426829).

Almost surely, 2^{216172018853657} is an apocalyptic number.

It is an amenable number.

216172018853657 is a deficient number, since it is larger than the sum of its proper divisors (1).

216172018853657 is an equidigital number, since it uses as much as digits as its factorization.

216172018853657 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 33868800, while the sum is 62.

The spelling of 216172018853657 in words is "two hundred sixteen trillion, one hundred seventy-two billion, eighteen million, eight hundred fifty-three thousand, six hundred fifty-seven".