99165821 has 8 divisors (see below), whose sum is σ = 100504800. Its totient is φ = 97835920.

The previous prime is 99165799. The next prime is 99165853. The reversal of 99165821 is 12856199.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 99165821 - 2¹⁸ = 98903677 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99165881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21335 + ... + 25563.

It is an arithmetic number, because the mean of its divisors is an integer number (12563100).

Almost surely, 2^99165821 is an apocalyptic number.

It is an amenable number.

99165821 is a deficient number, since it is larger than the sum of its proper divisors (1338979).

99165821 is a wasteful number, since it uses less digits than its factorization.

99165821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4539.

The product of its digits is 38880, while the sum is 41.

The square root of 99165821 is about 9958.2037034799. The cubic root of 99165821 is about 462.8646392474.

The spelling of 99165821 in words is "ninety-nine million, one hundred sixty-five thousand, eight hundred twenty-one".