99665280 has 384 divisors, whose sum is σ = 407665440. Its totient is φ = 22302720.

The previous prime is 99665263. The next prime is 99665299. The reversal of 99665280 is 8256699.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7666554 + ... + 7666566.

Almost surely, 2^99665280 is an apocalyptic number.

99665280 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

99665280 is the 4992-nd decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99665280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (203832720).

99665280 is an abundant number, since it is smaller than the sum of its proper divisors (308000160).

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

99665280 is a wasteful number, since it uses less digits than its factorization.

99665280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 99665280 is about 9983.2499718278. The cubic root of 99665280 is about 463.6404269330.

The spelling of 99665280 in words is "ninety-nine million, six hundred sixty-five thousand, two hundred eighty".