91865529216 has 320 divisors, whose sum is σ = 284555177280. Its totient is φ = 29396570112.

The previous prime is 91865529209. The next prime is 91865529221. The reversal of 91865529216 is 61292556819.

91865529216 is a `hidden beast` number, since 9 + 1 + 86 + 552 + 9 + 2 + 1 + 6 = 666.

It is a super-3 number, since 3×91865529216³ (a number of 34 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 25824910 + ... + 25828466.

It is an arithmetic number, because the mean of its divisors is an integer number (889234929).

Almost surely, 2^91865529216 is an apocalyptic number.

91865529216 is a gapful number since it is divisible by the number (96) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91865529216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142277588640).

91865529216 is an abundant number, since it is smaller than the sum of its proper divisors (192689648064).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91865529216 is a wasteful number, since it uses less digits than its factorization.

91865529216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3683 (or 3662 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 54.

The spelling of 91865529216 in words is "ninety-one billion, eight hundred sixty-five million, five hundred twenty-nine thousand, two hundred sixteen".