91998598 has 4 divisors (see below), whose sum is σ = 137997900. Its totient is φ = 45999298.

The previous prime is 91998593. The next prime is 91998601. The reversal of 91998598 is 89589919.

It is a happy number.

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

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91998593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22999648 + ... + 22999651.

It is an arithmetic number, because the mean of its divisors is an integer number (34499475).

Almost surely, 2^91998598 is an apocalyptic number.

91998598 is a deficient number, since it is larger than the sum of its proper divisors (45999302).

91998598 is a wasteful number, since it uses less digits than its factorization.

91998598 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45999301.

The product of its digits is 2099520, while the sum is 58.

The square root of 91998598 is about 9591.5899620449. The cubic root of 91998598 is about 451.4334503730.

The spelling of 91998598 in words is "ninety-one million, nine hundred ninety-eight thousand, five hundred ninety-eight".