91214221217 has 16 divisors (see below), whose sum is σ = 110133941760. Its totient is φ = 73881503808.

The previous prime is 91214221183. The next prime is 91214221247. The reversal of 91214221217 is 71212241219.

It is not a de Polignac number, because 91214221217 - 2¹⁰ = 91214220193 is a prime.

It is a super-2 number, since 2×91214221217² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91214221247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4770578 + ... + 4789659.

It is an arithmetic number, because the mean of its divisors is an integer number (6883371360).

Almost surely, 2^91214221217 is an apocalyptic number.

It is an amenable number.

91214221217 is a deficient number, since it is larger than the sum of its proper divisors (18919720543).

91214221217 is a wasteful number, since it uses less digits than its factorization.

91214221217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9560320.

The product of its digits is 4032, while the sum is 32.

The spelling of 91214221217 in words is "ninety-one billion, two hundred fourteen million, two hundred twenty-one thousand, two hundred seventeen".