1991459598 has 8 divisors (see below), whose sum is σ = 3982919208. Its totient is φ = 663819864.

The previous prime is 1991459579. The next prime is 1991459633. The reversal of 1991459598 is 8959541991.

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

1991459598 is an admirable number.

It is a super-2 number, since 2×1991459598² = 7931822660932643208, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165954961 + ... + 165954972.

It is an arithmetic number, because the mean of its divisors is an integer number (497864901).

Almost surely, 2^1991459598 is an apocalyptic number.

1991459598 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1991459598 is a wasteful number, since it uses less digits than its factorization.

1991459598 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331909938.

The product of its digits is 5248800, while the sum is 60.

The square root of 1991459598 is about 44625.7728000311. The cubic root of 1991459598 is about 1258.1251190930.

The spelling of 1991459598 in words is "one billion, nine hundred ninety-one million, four hundred fifty-nine thousand, five hundred ninety-eight".