99021917 has 4 divisors (see below), whose sum is σ = 99041820. Its totient is φ = 99002016.

The previous prime is 99021911. The next prime is 99021943. The reversal of 99021917 is 71912099.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 16048036 + 82973881 = 4006^2 + 9109^2 .

It is a cyclic number.

It is not a de Polignac number, because 99021917 - 2¹⁰ = 99020893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99021911) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 4943 + ... + 14915.

It is an arithmetic number, because the mean of its divisors is an integer number (24760455).

Almost surely, 2^99021917 is an apocalyptic number.

It is an amenable number.

99021917 is a deficient number, since it is larger than the sum of its proper divisors (19903).

99021917 is an equidigital number, since it uses as much as digits as its factorization.

99021917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19902.

The product of its (nonzero) digits is 10206, while the sum is 38.

The square root of 99021917 is about 9950.9756808064. The cubic root of 99021917 is about 462.6406362670.

The spelling of 99021917 in words is "ninety-nine million, twenty-one thousand, nine hundred seventeen".