216069665 has 12 divisors (see below), whose sum is σ = 301615956. Its totient is φ = 148161888.

The previous prime is 216069649. The next prime is 216069671. The reversal of 216069665 is 566960612.

It can be written as a sum of positive squares in 2 ways, for example, as 170250304 + 45819361 = 13048^2 + 6769^2 .

It is not a de Polignac number, because 216069665 - 2⁴ = 216069649 is a prime.

It is a super-2 number, since 2×216069665² = 93372200266424450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 440714 + ... + 441203.

It is an arithmetic number, because the mean of its divisors is an integer number (25134663).

Almost surely, 2^216069665 is an apocalyptic number.

It is an amenable number.

216069665 is a deficient number, since it is larger than the sum of its proper divisors (85546291).

216069665 is an equidigital number, since it uses as much as digits as its factorization.

216069665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881936 (or 881929 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 216069665 is about 14699.3083170604. The cubic root of 216069665 is about 600.0644976961.

The spelling of 216069665 in words is "two hundred sixteen million, sixty-nine thousand, six hundred sixty-five".