216601801 has 8 divisors (see below), whose sum is σ = 233399880. Its totient is φ = 199823232.

The previous prime is 216601769. The next prime is 216601817. The reversal of 216601801 is 108106612.

It can be written as a sum of positive squares in 4 ways, for example, as 42889401 + 173712400 = 6549^2 + 13180^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216601801 - 2⁵ = 216601769 is a prime.

It is a super-3 number, since 3×216601801³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216601871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25005 + ... + 32533.

It is an arithmetic number, because the mean of its divisors is an integer number (29174985).

Almost surely, 2^216601801 is an apocalyptic number.

It is an amenable number.

216601801 is a deficient number, since it is larger than the sum of its proper divisors (16798079).

216601801 is a wasteful number, since it uses less digits than its factorization.

216601801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9755.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 216601801 is about 14717.3979018032. The cubic root of 216601801 is about 600.5567064516.

The spelling of 216601801 in words is "two hundred sixteen million, six hundred one thousand, eight hundred one".