71778419 has 2 divisors, whose sum is σ = 71778420. Its totient is φ = 71778418.

The previous prime is 71778407. The next prime is 71778449. The reversal of 71778419 is 91487717.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71778419 is a prime.

It is a super-2 number, since 2×71778419² = 10304282868279122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71778419.

It is not a weakly prime, because it can be changed into another prime (71778449) 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, 35889209 + 35889210.

It is an arithmetic number, because the mean of its divisors is an integer number (35889210).

Almost surely, 2^71778419 is an apocalyptic number.

71778419 is a deficient number, since it is larger than the sum of its proper divisors (1).

71778419 is an equidigital number, since it uses as much as digits as its factorization.

71778419 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 98784, while the sum is 44.

The square root of 71778419 is about 8472.2145275011. The cubic root of 71778419 is about 415.5895602774.

The spelling of 71778419 in words is "seventy-one million, seven hundred seventy-eight thousand, four hundred nineteen".