91544955840 has 560 divisors, whose sum is σ = 352365064128. Its totient is φ = 22426730496.

The previous prime is 91544955767. The next prime is 91544955869. The reversal of 91544955840 is 4855944519.

91544955840 is a `hidden beast` number, since 9 + 1 + 5 + 4 + 49 + 558 + 40 = 666.

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

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 88619964 + ... + 88620996.

Almost surely, 2^91544955840 is an apocalyptic number.

91544955840 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 91544955840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176182532064).

91544955840 is an abundant number, since it is smaller than the sum of its proper divisors (260820108288).

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

91544955840 is a wasteful number, since it uses less digits than its factorization.

91544955840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338 (or 1319 counting only the distinct ones).

The product of its (nonzero) digits is 5184000, while the sum is 54.

The spelling of 91544955840 in words is "ninety-one billion, five hundred forty-four million, nine hundred fifty-five thousand, eight hundred forty".