75165661 has 2 divisors, whose sum is σ = 75165662. Its totient is φ = 75165660.

The previous prime is 75165659. The next prime is 75165689. The reversal of 75165661 is 16656157.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66928761 + 8236900 = 8181^2 + 2870^2 .

It is a cyclic number.

It is not a de Polignac number, because 75165661 - 2¹ = 75165659 is a prime.

Together with 75165659, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 75165661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (75165631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 37582830 + 37582831.

It is an arithmetic number, because the mean of its divisors is an integer number (37582831).

Almost surely, 2^75165661 is an apocalyptic number.

It is an amenable number.

75165661 is a deficient number, since it is larger than the sum of its proper divisors (1).

75165661 is an equidigital number, since it uses as much as digits as its factorization.

75165661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37800, while the sum is 37.

The square root of 75165661 is about 8669.8132044468. The cubic root of 75165661 is about 422.0266018734.

The spelling of 75165661 in words is "seventy-five million, one hundred sixty-five thousand, six hundred sixty-one".