216519705 has 12 divisors (see below), whose sum is σ = 375300900. Its totient is φ = 115477152.

The previous prime is 216519703. The next prime is 216519727. The reversal of 216519705 is 507915612.

It can be written as a sum of positive squares in 2 ways, for example, as 116899344 + 99620361 = 10812^2 + 9981^2 .

It is not a de Polignac number, because 216519705 - 2¹ = 216519703 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 216519705.

It is not an unprimeable number, because it can be changed into a prime (216519703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2405730 + ... + 2405819.

It is an arithmetic number, because the mean of its divisors is an integer number (31275075).

Almost surely, 2^216519705 is an apocalyptic number.

It is an amenable number.

216519705 is a deficient number, since it is larger than the sum of its proper divisors (158781195).

216519705 is a wasteful number, since it uses less digits than its factorization.

216519705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4811560 (or 4811557 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 36.

The square root of 216519705 is about 14714.6085574846. The cubic root of 216519705 is about 600.4808229126.

The spelling of 216519705 in words is "two hundred sixteen million, five hundred nineteen thousand, seven hundred five".