71665801 has 2 divisors, whose sum is σ = 71665802. Its totient is φ = 71665800.

The previous prime is 71665787. The next prime is 71665817. The reversal of 71665801 is 10856617.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 69705801 + 1960000 = 8349^2 + 1400^2 .

It is a cyclic number.

It is not a de Polignac number, because 71665801 - 2¹³ = 71657609 is a prime.

It is a plaindrome in base 16.

It is not a weakly prime, because it can be changed into another prime (71665201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35832900 + 35832901.

It is an arithmetic number, because the mean of its divisors is an integer number (35832901).

Almost surely, 2^71665801 is an apocalyptic number.

It is an amenable number.

71665801 is a deficient number, since it is larger than the sum of its proper divisors (1).

71665801 is an equidigital number, since it uses as much as digits as its factorization.

71665801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 71665801 is about 8465.5656042582. The cubic root of 71665801 is about 415.3720976821.

The spelling of 71665801 in words is "seventy-one million, six hundred sixty-five thousand, eight hundred one".