71437661 has 2 divisors, whose sum is σ = 71437662. Its totient is φ = 71437660.

The previous prime is 71437657. The next prime is 71437699. The reversal of 71437661 is 16673417.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37576900 + 33860761 = 6130^2 + 5819^2 .

It is a cyclic number.

It is not a de Polignac number, because 71437661 - 2² = 71437657 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71437601) 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, 35718830 + 35718831.

It is an arithmetic number, because the mean of its divisors is an integer number (35718831).

Almost surely, 2^71437661 is an apocalyptic number.

It is an amenable number.

71437661 is a deficient number, since it is larger than the sum of its proper divisors (1).

71437661 is an equidigital number, since it uses as much as digits as its factorization.

71437661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 35.

The square root of 71437661 is about 8452.0802764763. The cubic root of 71437661 is about 414.9308657276.

The spelling of 71437661 in words is "seventy-one million, four hundred thirty-seven thousand, six hundred sixty-one".