99900900998 has 4 divisors (see below), whose sum is σ = 149851351500. Its totient is φ = 49950450498.

The previous prime is 99900900997. The next prime is 99900901003. The reversal of 99900900998 is 89900900999.

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

It is a self number, because there is not a number n which added to its sum of digits gives 99900900998.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99900900997) 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 as a sum of consecutive naturals, namely, 24975225248 + ... + 24975225251.

It is an arithmetic number, because the mean of its divisors is an integer number (37462837875).

Almost surely, 2^99900900998 is an apocalyptic number.

99900900998 is a deficient number, since it is larger than the sum of its proper divisors (49950450502).

99900900998 is a wasteful number, since it uses less digits than its factorization.

99900900998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49950450501.

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

Subtracting from 99900900998 its reverse (89900900999), we obtain a palindrome (9999999999).

The spelling of 99900900998 in words is "ninety-nine billion, nine hundred million, nine hundred thousand, nine hundred ninety-eight".