5217216661 has 4 divisors (see below), whose sum is σ = 5444052192. Its totient is φ = 4990381132.

The previous prime is 5217216647. The next prime is 5217216677. The reversal of 5217216661 is 1666127125.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 5217216661 - 2¹⁷ = 5217085589 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 5217216661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5217216691) 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 3 ways as a sum of consecutive naturals, for example, 113417731 + ... + 113417776.

It is an arithmetic number, because the mean of its divisors is an integer number (1361013048).

Almost surely, 2^5217216661 is an apocalyptic number.

It is an amenable number.

5217216661 is a deficient number, since it is larger than the sum of its proper divisors (226835531).

5217216661 is a wasteful number, since it uses less digits than its factorization.

5217216661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226835530.

The product of its digits is 30240, while the sum is 37.

The square root of 5217216661 is about 72230.3029275110. The cubic root of 5217216661 is about 1734.3881229821.

The spelling of 5217216661 in words is "five billion, two hundred seventeen million, two hundred sixteen thousand, six hundred sixty-one".