101665649 has 2 divisors, whose sum is σ = 101665650. Its totient is φ = 101665648.

The previous prime is 101665639. The next prime is 101665667. The reversal of 101665649 is 946566101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86118400 + 15547249 = 9280^2 + 3943^2 .

It is a cyclic number.

It is not a de Polignac number, because 101665649 - 2²⁰ = 100617073 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (101665639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50832824 + 50832825.

It is an arithmetic number, because the mean of its divisors is an integer number (50832825).

Almost surely, 2^101665649 is an apocalyptic number.

It is an amenable number.

101665649 is a deficient number, since it is larger than the sum of its proper divisors (1).

101665649 is an equidigital number, since it uses as much as digits as its factorization.

101665649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 101665649 is about 10082.9385101765. The cubic root of 101665649 is about 466.7217918441.

The spelling of 101665649 in words is "one hundred one million, six hundred sixty-five thousand, six hundred forty-nine".