91755555840 has 1232 divisors, whose sum is σ = 372871301376. Its totient is φ = 21499084800.

The previous prime is 91755555833. The next prime is 91755555889. The reversal of 91755555840 is 4855555719.

91755555840 is a `hidden beast` number, since 9 + 1 + 7 + 5 + 5 + 55 + 584 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 1504189410 + ... + 1504189470.

Almost surely, 2^91755555840 is an apocalyptic number.

91755555840 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 91755555840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (186435650688).

91755555840 is an abundant number, since it is smaller than the sum of its proper divisors (281115745536).

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

91755555840 is a wasteful number, since it uses less digits than its factorization.

91755555840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 115 counting only the distinct ones).

The product of its (nonzero) digits is 6300000, while the sum is 54.

The spelling of 91755555840 in words is "ninety-one billion, seven hundred fifty-five million, five hundred fifty-five thousand, eight hundred forty".