91208216517 has 8 divisors (see below), whose sum is σ = 132666496800. Its totient is φ = 55277706960.

The previous prime is 91208216483. The next prime is 91208216551. The reversal of 91208216517 is 71561280219.

It is an interprime number because it is at equal distance from previous prime (91208216483) and next prime (91208216551).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 91208216517 - 2⁶ = 91208216453 is a prime.

It is a super-2 number, since 2×91208216517² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91208216557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1381942642 + ... + 1381942707.

It is an arithmetic number, because the mean of its divisors is an integer number (16583312100).

Almost surely, 2^91208216517 is an apocalyptic number.

It is an amenable number.

91208216517 is a deficient number, since it is larger than the sum of its proper divisors (41458280283).

91208216517 is a wasteful number, since it uses less digits than its factorization.

91208216517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2763885363.

The product of its (nonzero) digits is 60480, while the sum is 42.

The spelling of 91208216517 in words is "ninety-one billion, two hundred eight million, two hundred sixteen thousand, five hundred seventeen".