2023661 has 2 divisors, whose sum is σ = 2023662. Its totient is φ = 2023660.

The previous prime is 2023639. The next prime is 2023667. The reversal of 2023661 is 1663202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1525225 + 498436 = 1235^2 + 706^2 .

It is a cyclic number.

It is not a de Polignac number, because 2023661 - 2⁶ = 2023597 is a prime.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2023667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1011830 + 1011831.

It is an arithmetic number, because the mean of its divisors is an integer number (1011831).

2^2023661 is an apocalyptic number.

It is an amenable number.

2023661 is a deficient number, since it is larger than the sum of its proper divisors (1).

2023661 is an equidigital number, since it uses as much as digits as its factorization.

2023661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 2023661 is about 1422.5543926332. The cubic root of 2023661 is about 126.4870083051.

Adding to 2023661 its reverse (1663202), we get a palindrome (3686863).

The spelling of 2023661 in words is "two million, twenty-three thousand, six hundred sixty-one".