1991859098 has 8 divisors (see below), whose sum is σ = 2993503008. Its totient is φ = 994024764.

The previous prime is 1991859083. The next prime is 1991859109. The reversal of 1991859098 is 8909581991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 951086 + ... + 953177.

It is an arithmetic number, because the mean of its divisors is an integer number (374187876).

Almost surely, 2^1991859098 is an apocalyptic number.

1991859098 is a deficient number, since it is larger than the sum of its proper divisors (1001643910).

1991859098 is a wasteful number, since it uses less digits than its factorization.

1991859098 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1904788.

The product of its (nonzero) digits is 2099520, while the sum is 59.

The square root of 1991859098 is about 44630.2486885296. The cubic root of 1991859098 is about 1258.2092428817.

The spelling of 1991859098 in words is "one billion, nine hundred ninety-one million, eight hundred fifty-nine thousand, ninety-eight".