216855077 has 8 divisors (see below), whose sum is σ = 229757976. Its totient is φ = 203968512.

The previous prime is 216855071. The next prime is 216855091. The reversal of 216855077 is 770558612.

It is a Cunningham number, because it is equal to 14726²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 1 + 216855076 = 1^2 + 14726^2 .

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 216855077 - 2⁸ = 216854821 is a prime.

It is a super-2 number, since 2×216855077² = 94052248841351858, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216855071) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32903 + ... + 38939.

It is an arithmetic number, because the mean of its divisors is an integer number (28719747).

Almost surely, 2^216855077 is an apocalyptic number.

It is an amenable number.

216855077 is a deficient number, since it is larger than the sum of its proper divisors (12902899).

216855077 is a wasteful number, since it uses less digits than its factorization.

216855077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8167.

The product of its (nonzero) digits is 117600, while the sum is 41.

The square root of 216855077 is about 14726.0000339536. Note that the first 4 decimals coincide. The cubic root of 216855077 is about 600.7906955063.

It can be divided in two parts, 21685 and 5077, that added together give a palindrome (26762).

The spelling of 216855077 in words is "two hundred sixteen million, eight hundred fifty-five thousand, seventy-seven".