840451 has 2 divisors, whose sum is σ = 840452. Its totient is φ = 840450.

The previous prime is 840439. The next prime is 840457. The reversal of 840451 is 154048.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 840451 - 2¹¹ = 838403 is a prime.

It is not a weakly prime, because it can be changed into another prime (840457) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420225 + 420226.

It is an arithmetic number, because the mean of its divisors is an integer number (420226).

2⁸⁴⁰⁴⁵¹ is an apocalyptic number.

840451 is a deficient number, since it is larger than the sum of its proper divisors (1).

840451 is an equidigital number, since it uses as much as digits as its factorization.

840451 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 840451 is about 916.7611466462. The cubic root of 840451 is about 94.3707629342.

Adding to 840451 its reverse (154048), we get a palindrome (994499).

The spelling of 840451 in words is "eight hundred forty thousand, four hundred fifty-one".