991202131311 has 16 divisors (see below), whose sum is σ = 1527374073600. Its totient is φ = 560037158208.

The previous prime is 991202131243. The next prime is 991202131457. The reversal of 991202131311 is 113131202199.

It is a happy number.

991202131311 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 991202131311 - 2¹¹ = 991202129263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991202135311) 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, 265167241 + ... + 265170978.

It is an arithmetic number, because the mean of its divisors is an integer number (95460879600).

Almost surely, 2^991202131311 is an apocalyptic number.

991202131311 is a deficient number, since it is larger than the sum of its proper divisors (536171942289).

991202131311 is a wasteful number, since it uses less digits than its factorization.

991202131311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530338318.

The product of its (nonzero) digits is 2916, while the sum is 33.

The spelling of 991202131311 in words is "nine hundred ninety-one billion, two hundred two million, one hundred thirty-one thousand, three hundred eleven".