1100391 has 8 divisors (see below), whose sum is σ = 1486080. Its totient is φ = 724152.

The previous prime is 1100387. The next prime is 1100419. The reversal of 1100391 is 1930011.

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

It is not a de Polignac number, because 1100391 - 2² = 1100387 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1100391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1100311) 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, 2085 + ... + 2558.

It is an arithmetic number, because the mean of its divisors is an integer number (185760).

2^1100391 is an apocalyptic number.

1100391 is a deficient number, since it is larger than the sum of its proper divisors (385689).

1100391 is an equidigital number, since it uses as much as digits as its factorization.

1100391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4725.

The product of its (nonzero) digits is 27, while the sum is 15.

The square root of 1100391 is about 1048.9952335449. The cubic root of 1100391 is about 103.2402410520.

The spelling of 1100391 in words is "one million, one hundred thousand, three hundred ninety-one".