99990221 has 8 divisors (see below), whose sum is σ = 104524800. Its totient is φ = 95537520.

The previous prime is 99990181. The next prime is 99990239. The reversal of 99990221 is 12209999.

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 99990221 - 2¹⁸ = 99728077 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 (99990281) 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, 17966 + ... + 22863.

It is an arithmetic number, because the mean of its divisors is an integer number (13065600).

Almost surely, 2^99990221 is an apocalyptic number.

It is an amenable number.

99990221 is a deficient number, since it is larger than the sum of its proper divisors (4534579).

99990221 is a wasteful number, since it uses less digits than its factorization.

99990221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40939.

The product of its (nonzero) digits is 26244, while the sum is 41.

The square root of 99990221 is about 9999.5110380458. The cubic root of 99990221 is about 464.1437528357.

The spelling of 99990221 in words is "ninety-nine million, nine hundred ninety thousand, two hundred twenty-one".