991102001 has 8 divisors (see below), whose sum is σ = 1008469440. Its totient is φ = 973753648.

The previous prime is 991101973. The next prime is 991102003. The reversal of 991102001 is 100201199.

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

It is a cyclic number.

It is not a de Polignac number, because 991102001 - 2²⁶ = 923993137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (991102003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135500 + ... + 142626.

It is an arithmetic number, because the mean of its divisors is an integer number (126058680).

Almost surely, 2^991102001 is an apocalyptic number.

It is an amenable number.

991102001 is a deficient number, since it is larger than the sum of its proper divisors (17367439).

991102001 is a wasteful number, since it uses less digits than its factorization.

991102001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9543.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 991102001 is about 31481.7725199837. The cubic root of 991102001 is about 997.0251594324.

The spelling of 991102001 in words is "nine hundred ninety-one million, one hundred two thousand, one".