991108912101 has 32 divisors (see below), whose sum is σ = 1653505640448. Its totient is φ = 513003032640.

The previous prime is 991108912033. The next prime is 991108912103. The reversal of 991108912101 is 101219801199.

It is not a de Polignac number, because 991108912101 - 2¹⁴ = 991108895717 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991108912103) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7680625 + ... + 7808598.

It is an arithmetic number, because the mean of its divisors is an integer number (51672051264).

Almost surely, 2^991108912101 is an apocalyptic number.

It is an amenable number.

991108912101 is a deficient number, since it is larger than the sum of its proper divisors (662396728347).

991108912101 is a wasteful number, since it uses less digits than its factorization.

991108912101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15489521.

The product of its (nonzero) digits is 11664, while the sum is 42.

The spelling of 991108912101 in words is "nine hundred ninety-one billion, one hundred eight million, nine hundred twelve thousand, one hundred one".