100731661 has 2 divisors, whose sum is σ = 100731662. Its totient is φ = 100731660.

The previous prime is 100731637. The next prime is 100731677. The reversal of 100731661 is 166137001.

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., 95062500 + 5669161 = 9750^2 + 2381^2 .

It is a cyclic number.

It is not a de Polignac number, because 100731661 - 2⁹ = 100731149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100731061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50365830 + 50365831.

It is an arithmetic number, because the mean of its divisors is an integer number (50365831).

Almost surely, 2^100731661 is an apocalyptic number.

It is an amenable number.

100731661 is a deficient number, since it is larger than the sum of its proper divisors (1).

100731661 is an equidigital number, since it uses as much as digits as its factorization.

100731661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 100731661 is about 10036.5163777080. The cubic root of 100731661 is about 465.2881568476.

Adding to 100731661 its reverse (166137001), we get a palindrome (266868662).

The spelling of 100731661 in words is "one hundred million, seven hundred thirty-one thousand, six hundred sixty-one".