71405861 has 2 divisors, whose sum is σ = 71405862. Its totient is φ = 71405860.

The previous prime is 71405849. The next prime is 71405909. The reversal of 71405861 is 16850417.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67141636 + 4264225 = 8194^2 + 2065^2 .

It is a cyclic number.

It is not a de Polignac number, because 71405861 - 2²⁶ = 4296997 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71405821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35702930 + 35702931.

It is an arithmetic number, because the mean of its divisors is an integer number (35702931).

Almost surely, 2^71405861 is an apocalyptic number.

It is an amenable number.

71405861 is a deficient number, since it is larger than the sum of its proper divisors (1).

71405861 is an equidigital number, since it uses as much as digits as its factorization.

71405861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 32.

The square root of 71405861 is about 8450.1988733994. The cubic root of 71405861 is about 414.8692886841.

The spelling of 71405861 in words is "seventy-one million, four hundred five thousand, eight hundred sixty-one".