91165415040 has 384 divisors, whose sum is σ = 371388625920. Its totient is φ = 20165345280.

The previous prime is 91165415023. The next prime is 91165415053. The reversal of 91165415040 is 4051456119.

91165415040 is a `hidden beast` number, since 91 + 1 + 65 + 4 + 1 + 504 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×91165415040² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 91165414986 and 91165415004.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 1213452 + ... + 1286388.

It is an arithmetic number, because the mean of its divisors is an integer number (967157880).

Almost surely, 2^91165415040 is an apocalyptic number.

91165415040 is a gapful number since it is divisible by the number (90) 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 91165415040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (185694312960).

91165415040 is an abundant number, since it is smaller than the sum of its proper divisors (280223210880).

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

91165415040 is a wasteful number, since it uses less digits than its factorization.

91165415040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73000 (or 72985 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The spelling of 91165415040 in words is "ninety-one billion, one hundred sixty-five million, four hundred fifteen thousand, forty".