1999498591 has 2 divisors, whose sum is σ = 1999498592. Its totient is φ = 1999498590.

The previous prime is 1999498577. The next prime is 1999498691. The reversal of 1999498591 is 1958949991.

It is a weak prime.

It is an emirp because it is prime and its reverse (1958949991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1999498591 - 2¹⁵ = 1999465823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1999498531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999749295 + 999749296.

It is an arithmetic number, because the mean of its divisors is an integer number (999749296).

Almost surely, 2^1999498591 is an apocalyptic number.

1999498591 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999498591 is an equidigital number, since it uses as much as digits as its factorization.

1999498591 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9447840, while the sum is 64.

The square root of 1999498591 is about 44715.7532755516. The cubic root of 1999498591 is about 1259.8157518025.

The spelling of 1999498591 in words is "one billion, nine hundred ninety-nine million, four hundred ninety-eight thousand, five hundred ninety-one".