415661 has 2 divisors, whose sum is σ = 415662. Its totient is φ = 415660.

The previous prime is 415651. The next prime is 415669. The reversal of 415661 is 166514.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 240100 + 175561 = 490^2 + 419^2 .

It is a cyclic number.

It is not a de Polignac number, because 415661 - 2¹⁴ = 399277 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (415669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 207830 + 207831.

It is an arithmetic number, because the mean of its divisors is an integer number (207831).

2⁴¹⁵⁶⁶¹ is an apocalyptic number.

It is an amenable number.

415661 is a deficient number, since it is larger than the sum of its proper divisors (1).

415661 is an equidigital number, since it uses as much as digits as its factorization.

415661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 720, while the sum is 23.

The square root of 415661 is about 644.7177677093. The cubic root of 415661 is about 74.6299400411.

The spelling of 415661 in words is "four hundred fifteen thousand, six hundred sixty-one".