1198109691 has 16 divisors (see below), whose sum is σ = 1822951200. Its totient is φ = 777151584.

The previous prime is 1198109681. The next prime is 1198109707. The reversal of 1198109691 is 1969018911.

It is not a de Polignac number, because 1198109691 - 2⁵ = 1198109659 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (1198109641) 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, 598656 + ... + 600653.

It is an arithmetic number, because the mean of its divisors is an integer number (113934450).

Almost surely, 2^1198109691 is an apocalyptic number.

1198109691 is a deficient number, since it is larger than the sum of its proper divisors (624841509).

1198109691 is a wasteful number, since it uses less digits than its factorization.

1198109691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1199355 (or 1199349 counting only the distinct ones).

The product of its (nonzero) digits is 34992, while the sum is 45.

The square root of 1198109691 is about 34613.7211377222. The cubic root of 1198109691 is about 1062.1002889745.

It can be divided in two parts, 1198 and 109691, that added together give a square (110889 = 333²).

The spelling of 1198109691 in words is "one billion, one hundred ninety-eight million, one hundred nine thousand, six hundred ninety-one".