991135531199 has 8 divisors (see below), whose sum is σ = 1096467477120. Its totient is φ = 888341704600.

The previous prime is 991135531157. The next prime is 991135531201.

991135531199 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 991135531199 - 2⁸ = 991135530943 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 (991135531499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 634529009 + ... + 634530570.

It is an arithmetic number, because the mean of its divisors is an integer number (137058434640).

Almost surely, 2^991135531199 is an apocalyptic number.

991135531199 is a deficient number, since it is larger than the sum of its proper divisors (105331945921).

991135531199 is a wasteful number, since it uses less digits than its factorization.

991135531199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1269059661.

The product of its digits is 1476225, while the sum is 56.

The spelling of 991135531199 in words is "nine hundred ninety-one billion, one hundred thirty-five million, five hundred thirty-one thousand, one hundred ninety-nine".