99171543240 has 640 divisors, whose sum is σ = 429015121920. Its totient is φ = 19940774400.

The previous prime is 99171543217. The next prime is 99171543269. The reversal of 99171543240 is 4234517199.

99171543240 is a `hidden beast` number, since 9 + 9 + 171 + 5 + 432 + 40 = 666.

It is a super-3 number, since 3×99171543240³ (a number of 34 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 159 ways as a sum of consecutive naturals, for example, 7727469 + ... + 7740291.

It is an arithmetic number, because the mean of its divisors is an integer number (670336128).

Almost surely, 2^99171543240 is an apocalyptic number.

99171543240 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 99171543240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (214507560960).

99171543240 is an abundant number, since it is smaller than the sum of its proper divisors (329843578680).

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

99171543240 is a wasteful number, since it uses less digits than its factorization.

99171543240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12895 (or 12882 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

It can be divided in two parts, 99171 and 543240, that added together give a triangular number (642411 = T₁₁₃₃).

The spelling of 99171543240 in words is "ninety-nine billion, one hundred seventy-one million, five hundred forty-three thousand, two hundred forty".