991438834199 has 16 divisors (see below), whose sum is σ = 1089960952320. Its totient is φ = 894342120000.

The previous prime is 991438834193. The next prime is 991438834229.

991438834199 is nontrivially palindromic in base 10.

991438834199 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 991438834199 - 2¹² = 991438830103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991438834193) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67724 + ... + 1409774.

It is an arithmetic number, because the mean of its divisors is an integer number (68122559520).

Almost surely, 2^991438834199 is an apocalyptic number.

991438834199 is a deficient number, since it is larger than the sum of its proper divisors (98522118121).

991438834199 is a wasteful number, since it uses less digits than its factorization.

991438834199 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342582.

The product of its digits is 60466176, while the sum is 68.

The spelling of 991438834199 in words is "nine hundred ninety-one billion, four hundred thirty-eight million, eight hundred thirty-four thousand, one hundred ninety-nine".