107665721 has 2 divisors, whose sum is σ = 107665722. Its totient is φ = 107665720.

The previous prime is 107665711. The next prime is 107665739. The reversal of 107665721 is 127566701.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76807696 + 30858025 = 8764^2 + 5555^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-107665721 is a prime.

It is not a weakly prime, because it can be changed into another prime (107665711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53832860 + 53832861.

It is an arithmetic number, because the mean of its divisors is an integer number (53832861).

Almost surely, 2^107665721 is an apocalyptic number.

It is an amenable number.

107665721 is a deficient number, since it is larger than the sum of its proper divisors (1).

107665721 is an equidigital number, since it uses as much as digits as its factorization.

107665721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17640, while the sum is 35.

The square root of 107665721 is about 10376.2093752969. The cubic root of 107665721 is about 475.7284792488.

The spelling of 107665721 in words is "one hundred seven million, six hundred sixty-five thousand, seven hundred twenty-one".