91157760 has 216 divisors, whose sum is σ = 324762984. Its totient is φ = 23592960.

The previous prime is 91157747. The next prime is 91157767. The reversal of 91157760 is 6775119.

It can be written as a sum of positive squares in 4 ways, for example, as 831744 + 90326016 = 912^2 + 9504^2 .

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91157767) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 472224 + ... + 472416.

Almost surely, 2^91157760 is an apocalyptic number.

91157760 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 91157760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162381492).

91157760 is an abundant number, since it is smaller than the sum of its proper divisors (233605224).

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

91157760 is a wasteful number, since it uses less digits than its factorization.

91157760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 13230, while the sum is 36.

The square root of 91157760 is about 9547.6573042815. The cubic root of 91157760 is about 450.0539194650.

The spelling of 91157760 in words is "ninety-one million, one hundred fifty-seven thousand, seven hundred sixty".