216107661 has 16 divisors (see below), whose sum is σ = 359244288. Its totient is φ = 112263600.

The previous prime is 216107627. The next prime is 216107669. The reversal of 216107661 is 166701612.

It is not a de Polignac number, because 216107661 - 2⁷ = 216107533 is a prime.

It is a super-2 number, since 2×216107661² = 93405042285781842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216107669) 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 15 ways as a sum of consecutive naturals, for example, 467535 + ... + 467996.

It is an arithmetic number, because the mean of its divisors is an integer number (22452768).

Almost surely, 2^216107661 is an apocalyptic number.

216107661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

216107661 is a deficient number, since it is larger than the sum of its proper divisors (143136627).

216107661 is a wasteful number, since it uses less digits than its factorization.

216107661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935552.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 216107661 is about 14700.6007020121. The cubic root of 216107661 is about 600.0996695535.

The spelling of 216107661 in words is "two hundred sixteen million, one hundred seven thousand, six hundred sixty-one".