98981809 has 4 divisors (see below), whose sum is σ = 99534960. Its totient is φ = 98428660.

The previous prime is 98981801. The next prime is 98981819. The reversal of 98981809 is 90818989.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 90818989 = 977 ⋅92957.

It is a cyclic number.

It is not a de Polignac number, because 98981809 - 2³ = 98981801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (98981801) 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, 276307 + ... + 276664.

It is an arithmetic number, because the mean of its divisors is an integer number (24883740).

Almost surely, 2^98981809 is an apocalyptic number.

It is an amenable number.

98981809 is a deficient number, since it is larger than the sum of its proper divisors (553151).

98981809 is a wasteful number, since it uses less digits than its factorization.

98981809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 553150.

The product of its (nonzero) digits is 373248, while the sum is 52.

The square root of 98981809 is about 9948.9601969251. The cubic root of 98981809 is about 462.5781649239.

Subtracting from 98981809 its reverse (90818989), we obtain a triangular number (8162820 = T₄₀₄₀).

The spelling of 98981809 in words is "ninety-eight million, nine hundred eighty-one thousand, eight hundred nine".