91115388 has 192 divisors, whose sum is σ = 297041920. Its totient is φ = 23514624.

The previous prime is 91115371. The next prime is 91115413. The reversal of 91115388 is 88351119.

91115388 is a `hidden beast` number, since 9 + 111 + 538 + 8 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 717381 + ... + 717507.

Almost surely, 2^91115388 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91115388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148520960).

91115388 is an abundant number, since it is smaller than the sum of its proper divisors (205926532).

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

91115388 is a wasteful number, since it uses less digits than its factorization.

91115388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 225 counting only the distinct ones).

The product of its digits is 8640, while the sum is 36.

The square root of 91115388 is about 9545.4380727131. The cubic root of 91115388 is about 449.9841772214.

The spelling of 91115388 in words is "ninety-one million, one hundred fifteen thousand, three hundred eighty-eight".