991109902 has 8 divisors (see below), whose sum is σ = 1486844712. Its totient is φ = 495495000.

The previous prime is 991109891. The next prime is 991109909. The reversal of 991109902 is 209901199.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991109909) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5224 + ... + 44827.

It is an arithmetic number, because the mean of its divisors is an integer number (185855589).

Almost surely, 2^991109902 is an apocalyptic number.

991109902 is a deficient number, since it is larger than the sum of its proper divisors (495734810).

991109902 is a wasteful number, since it uses less digits than its factorization.

991109902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59954.

The product of its (nonzero) digits is 13122, while the sum is 40.

The square root of 991109902 is about 31481.8980050441. The cubic root of 991109902 is about 997.0278088317.

The spelling of 991109902 in words is "nine hundred ninety-one million, one hundred nine thousand, nine hundred two".