999899398 has 4 divisors (see below), whose sum is σ = 1499849100. Its totient is φ = 499949698.

The previous prime is 999899333. The next prime is 999899399. The reversal of 999899398 is 893998999.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 893998999 = 251 ⋅3561749.

It is a super-2 number, since 2×999899398² = 1999597612241524808, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 999899398.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999899399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249974848 + ... + 249974851.

It is an arithmetic number, because the mean of its divisors is an integer number (374962275).

Almost surely, 2^999899398 is an apocalyptic number.

999899398 is a deficient number, since it is larger than the sum of its proper divisors (499949702).

999899398 is a wasteful number, since it uses less digits than its factorization.

999899398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499949701.

The product of its digits is 102036672, while the sum is 73.

The square root of 999899398 is about 31621.1859043901. The cubic root of 999899398 is about 999.9664648754.

The spelling of 999899398 in words is "nine hundred ninety-nine million, eight hundred ninety-nine thousand, three hundred ninety-eight".