1203661 has 2 divisors, whose sum is σ = 1203662. Its totient is φ = 1203660.

The previous prime is 1203641. The next prime is 1203667. The reversal of 1203661 is 1663021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 670761 + 532900 = 819^2 + 730^2 .

It is a cyclic number.

It is not a de Polignac number, because 1203661 - 2⁷ = 1203533 is a 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 (1203667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 601830 + 601831.

It is an arithmetic number, because the mean of its divisors is an integer number (601831).

2^1203661 is an apocalyptic number.

It is an amenable number.

1203661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1203661 is an equidigital number, since it uses as much as digits as its factorization.

1203661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 1203661 is about 1097.1148526932. The cubic root of 1203661 is about 106.3738136794.

Adding to 1203661 its reverse (1663021), we get a palindrome (2866682).

The spelling of 1203661 in words is "one million, two hundred three thousand, six hundred sixty-one".