99609997680 has 120 divisors (see below), whose sum is σ = 334741923360. Its totient is φ = 26545328640.

The previous prime is 99609997679. The next prime is 99609997717. The reversal of 99609997680 is 8679990699.

99609997680 is a `hidden beast` number, since 9 + 9 + 609 + 9 + 9 + 7 + 6 + 8 + 0 = 666.

99609997680 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (120).

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

It is a junction number, because it is equal to n+sod(n) for n = 99609997599 and 99609997608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1078110 + ... + 1166850.

It is an arithmetic number, because the mean of its divisors is an integer number (2789516028).

Almost surely, 2^99609997680 is an apocalyptic number.

99609997680 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 99609997680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167370961680).

99609997680 is an abundant number, since it is smaller than the sum of its proper divisors (235131925680).

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

99609997680 is a wasteful number, since it uses less digits than its factorization.

99609997680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90319 (or 90310 counting only the distinct ones).

The product of its (nonzero) digits is 119042784, while the sum is 72.

The spelling of 99609997680 in words is "ninety-nine billion, six hundred nine million, nine hundred ninety-seven thousand, six hundred eighty".