1000440391 has 2 divisors, whose sum is σ = 1000440392. Its totient is φ = 1000440390.

The previous prime is 1000440379. The next prime is 1000440439. The reversal of 1000440391 is 1930440001.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1000440391 - 2⁵ = 1000440359 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1000410391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 500220195 + 500220196.

It is an arithmetic number, because the mean of its divisors is an integer number (500220196).

Almost surely, 2^1000440391 is an apocalyptic number.

1000440391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1000440391 is an equidigital number, since it uses as much as digits as its factorization.

1000440391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 1000440391 is about 31629.7390283259. The cubic root of 1000440391 is about 1000.1467754559.

Adding to 1000440391 its reverse (1930440001), we get a palindrome (2930880392).

The spelling of 1000440391 in words is "one billion, four hundred forty thousand, three hundred ninety-one".