99165691376640 has 2816 divisors, whose sum is σ = 436162314240000. Its totient is φ = 20864718471168.

The previous prime is 99165691376551. The next prime is 99165691376641. The reversal of 99165691376640 is 4667319656199.

99165691376640 is a `hidden beast` number, since 9 + 9 + 1 + 6 + 569 + 13 + 7 + 6 + 6 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99165691376641) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 97316674051 + ... + 97316675069.

Almost surely, 2^{99165691376640} is an apocalyptic number.

99165691376640 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 99165691376640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (218081157120000).

99165691376640 is an abundant number, since it is smaller than the sum of its proper divisors (336996622863360).

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

99165691376640 is a wasteful number, since it uses less digits than its factorization.

99165691376640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1225 (or 1201 counting only the distinct ones).

The product of its (nonzero) digits is 396809280, while the sum is 72.

The spelling of 99165691376640 in words is "ninety-nine trillion, one hundred sixty-five billion, six hundred ninety-one million, three hundred seventy-six thousand, six hundred forty".