216257617 has 4 divisors (see below), whose sum is σ = 216296100. Its totient is φ = 216219136.

The previous prime is 216257603. The next prime is 216257623. The reversal of 216257617 is 716752612.

216257617 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 108076816 + 108180801 = 10396^2 + 10401^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216257617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216257117) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8992 + ... + 22657.

It is an arithmetic number, because the mean of its divisors is an integer number (54074025).

Almost surely, 2^216257617 is an apocalyptic number.

It is an amenable number.

216257617 is a deficient number, since it is larger than the sum of its proper divisors (38483).

216257617 is an equidigital number, since it uses as much as digits as its factorization.

216257617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38482.

The product of its digits is 35280, while the sum is 37.

The square root of 216257617 is about 14705.7001533419. The cubic root of 216257617 is about 600.2384394911.

The spelling of 216257617 in words is "two hundred sixteen million, two hundred fifty-seven thousand, six hundred seventeen".