1011391 has 2 divisors, whose sum is σ = 1011392. Its totient is φ = 1011390.

The previous prime is 1011377. The next prime is 1011397. The reversal of 1011391 is 1931101.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1931101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1011391 - 2⁵ = 1011359 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505695 + 505696.

It is an arithmetic number, because the mean of its divisors is an integer number (505696).

2^1011391 is an apocalyptic number.

1011391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011391 is an equidigital number, since it uses as much as digits as its factorization.

1011391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27, while the sum is 16.

The square root of 1011391 is about 1005.6793723648. The cubic root of 1011391 is about 100.3782673341.

Adding to 1011391 its reverse (1931101), we get a palindrome (2942492).

The spelling of 1011391 in words is "one million, eleven thousand, three hundred ninety-one".