3667561 has 2 divisors, whose sum is σ = 3667562. Its totient is φ = 3667560.

The previous prime is 3667553. The next prime is 3667567. The reversal of 3667561 is 1657663.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3385600 + 281961 = 1840^2 + 531^2 .

It is a cyclic number.

It is not a de Polignac number, because 3667561 - 2³ = 3667553 is a prime.

It is not a weakly prime, because it can be changed into another prime (3667567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1833780 + 1833781.

It is an arithmetic number, because the mean of its divisors is an integer number (1833781).

Almost surely, 2^3667561 is an apocalyptic number.

It is an amenable number.

3667561 is a deficient number, since it is larger than the sum of its proper divisors (1).

3667561 is an equidigital number, since it uses as much as digits as its factorization.

3667561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 34.

The square root of 3667561 is about 1915.0877264501. The cubic root of 3667561 is about 154.2147030570.

Adding to 3667561 its product of digits (22680), we get a square (3690241 = 1921²).

The spelling of 3667561 in words is "three million, six hundred sixty-seven thousand, five hundred sixty-one".