418721 has 2 divisors, whose sum is σ = 418722. Its totient is φ = 418720.

The previous prime is 418709. The next prime is 418739. The reversal of 418721 is 127814.

Added to its reverse (127814) it gives a triangular number (546535 = T₁₀₄₅).

418721 is nontrivially palindromic in base 8.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 286225 + 132496 = 535^2 + 364^2 .

It is a cyclic number.

It is not a de Polignac number, because 418721 - 2⁶ = 418657 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (418751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 209360 + 209361.

It is an arithmetic number, because the mean of its divisors is an integer number (209361).

2⁴¹⁸⁷²¹ is an apocalyptic number.

It is an amenable number.

418721 is a deficient number, since it is larger than the sum of its proper divisors (1).

418721 is an equidigital number, since it uses as much as digits as its factorization.

418721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 448, while the sum is 23.

The square root of 418721 is about 647.0865475344. The cubic root of 418721 is about 74.8126285788.

Adding to 418721 its reverse (127814), we get a triangular number (546535 = T₁₀₄₅).

The spelling of 418721 in words is "four hundred eighteen thousand, seven hundred twenty-one".