991231374101002 has 32 divisors (see below), whose sum is σ = 1507659259317120. Its totient is φ = 488719329691200.

The previous prime is 991231374100997. The next prime is 991231374101047. The reversal of 991231374101002 is 200101473132199.

It is a self number, because there is not a number n which added to its sum of digits gives 991231374101002.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 157925203 + ... + 164081785.

It is an arithmetic number, because the mean of its divisors is an integer number (47114351853660).

Almost surely, 2^{991231374101002} is an apocalyptic number.

991231374101002 is a deficient number, since it is larger than the sum of its proper divisors (516427885216118).

991231374101002 is a wasteful number, since it uses less digits than its factorization.

991231374101002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6159918.

The product of its (nonzero) digits is 81648, while the sum is 43.

The spelling of 991231374101002 in words is "nine hundred ninety-one trillion, two hundred thirty-one billion, three hundred seventy-four million, one hundred one thousand, two".