216670987 has 16 divisors (see below), whose sum is σ = 240210432. Its totient is φ = 194182560.

The previous prime is 216670939. The next prime is 216670991. The reversal of 216670987 is 789076612.

It is a happy number.

It is not a de Polignac number, because 216670987 - 2⁷ = 216670859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216670907) 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, 78688 + ... + 81394.

It is an arithmetic number, because the mean of its divisors is an integer number (15013152).

Almost surely, 2^216670987 is an apocalyptic number.

216670987 is a deficient number, since it is larger than the sum of its proper divisors (23539445).

216670987 is a wasteful number, since it uses less digits than its factorization.

216670987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2898.

The product of its (nonzero) digits is 254016, while the sum is 46.

The square root of 216670987 is about 14719.7481975746. The cubic root of 216670987 is about 600.6206420437.

Subtracting 216670987 from its reverse (789076612), we obtain a square (572405625 = 23925²).

It can be divided in two parts, 2166 and 70987, that added together give a triangular number (73153 = T₃₈₂).

The spelling of 216670987 in words is "two hundred sixteen million, six hundred seventy thousand, nine hundred eighty-seven".