71256643 has 2 divisors, whose sum is σ = 71256644. Its totient is φ = 71256642.

The previous prime is 71256629. The next prime is 71256671. The reversal of 71256643 is 34665217.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (34665217) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71256643 - 2⁹ = 71256131 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 71256599 and 71256608.

It is not a weakly prime, because it can be changed into another prime (71256613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35628321 + 35628322.

It is an arithmetic number, because the mean of its divisors is an integer number (35628322).

Almost surely, 2^71256643 is an apocalyptic number.

71256643 is a deficient number, since it is larger than the sum of its proper divisors (1).

71256643 is an equidigital number, since it uses as much as digits as its factorization.

71256643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 34.

The square root of 71256643 is about 8441.3649962550. The cubic root of 71256643 is about 414.5801007624.

The spelling of 71256643 in words is "seventy-one million, two hundred fifty-six thousand, six hundred forty-three".