216612061 has 8 divisors (see below), whose sum is σ = 222708024. Its totient is φ = 210554880.

The previous prime is 216612047. The next prime is 216612083. The reversal of 216612061 is 160216612.

216612061 = 328² + 329² + ... + 881².

It can be written as a sum of positive squares in 4 ways, for example, as 33524100 + 183087961 = 5790^2 + 13531^2 .

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 216612061 - 2⁵ = 216612029 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216612661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1821 + ... + 20893.

It is an arithmetic number, because the mean of its divisors is an integer number (27838503).

Almost surely, 2^216612061 is an apocalyptic number.

It is an amenable number.

216612061 is a deficient number, since it is larger than the sum of its proper divisors (6095963).

216612061 is a wasteful number, since it uses less digits than its factorization.

216612061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19391.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 216612061 is about 14717.7464647275. The cubic root of 216612061 is about 600.5661886974.

Adding to 216612061 its reverse (160216612), we get a palindrome (376828673).

The spelling of 216612061 in words is "two hundred sixteen million, six hundred twelve thousand, sixty-one".