71500661 has 2 divisors, whose sum is σ = 71500662. Its totient is φ = 71500660.

The previous prime is 71500577. The next prime is 71500669. The reversal of 71500661 is 16600517.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61324561 + 10176100 = 7831^2 + 3190^2 .

It is a cyclic number.

It is not a de Polignac number, because 71500661 - 2¹⁴ = 71484277 is a prime.

It is a super-2 number, since 2×71500661² = 10224689046873842, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 71500661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71500669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35750330 + 35750331.

It is an arithmetic number, because the mean of its divisors is an integer number (35750331).

Almost surely, 2^71500661 is an apocalyptic number.

It is an amenable number.

71500661 is a deficient number, since it is larger than the sum of its proper divisors (1).

71500661 is an equidigital number, since it uses as much as digits as its factorization.

71500661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 71500661 is about 8455.8063483029. The cubic root of 71500661 is about 415.0528040421.

The spelling of 71500661 in words is "seventy-one million, five hundred thousand, six hundred sixty-one".