90899999 has 4 divisors (see below), whose sum is σ = 90996336. Its totient is φ = 90803664.

The previous prime is 90899989. The next prime is 90900041. The reversal of 90899999 is 99999809.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90899999 is a prime.

It is a Duffinian number.

90899999 is a modest number, since divided by 9999 gives 9089 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90899989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46739 + ... + 48644.

It is an arithmetic number, because the mean of its divisors is an integer number (22749084).

Almost surely, 2^90899999 is an apocalyptic number.

90899999 is a deficient number, since it is larger than the sum of its proper divisors (96337).

90899999 is an equidigital number, since it uses as much as digits as its factorization.

90899999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96336.

The product of its (nonzero) digits is 4251528, while the sum is 62.

The square root of 90899999 is about 9534.1490967994. The cubic root of 90899999 is about 449.6293227304.

The spelling of 90899999 in words is "ninety million, eight hundred ninety-nine thousand, nine hundred ninety-nine".