1042391 has 4 divisors (see below), whose sum is σ = 1191312. Its totient is φ = 893472.

The previous prime is 1042381. The next prime is 1042399. The reversal of 1042391 is 1932401.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1042391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1042399) 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, 74450 + ... + 74463.

It is an arithmetic number, because the mean of its divisors is an integer number (297828).

2^1042391 is an apocalyptic number.

1042391 is a deficient number, since it is larger than the sum of its proper divisors (148921).

1042391 is an equidigital number, since it uses as much as digits as its factorization.

1042391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148920.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 1042391 is about 1020.9755139081. The cubic root of 1042391 is about 101.3935240377.

Adding to 1042391 its reverse (1932401), we get a palindrome (2974792).

The spelling of 1042391 in words is "one million, forty-two thousand, three hundred ninety-one".