71638471 has 2 divisors, whose sum is σ = 71638472. Its totient is φ = 71638470.

The previous prime is 71638433. The next prime is 71638507. The reversal of 71638471 is 17483617.

It is a strong prime.

It is an emirp because it is prime and its reverse (17483617) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71638471 - 2¹⁷ = 71507399 is a prime.

It is a super-3 number, since 3×71638471³ (a number of 25 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 71638471.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71635471) 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, 35819235 + 35819236.

It is an arithmetic number, because the mean of its divisors is an integer number (35819236).

Almost surely, 2^71638471 is an apocalyptic number.

71638471 is a deficient number, since it is larger than the sum of its proper divisors (1).

71638471 is an equidigital number, since it uses as much as digits as its factorization.

71638471 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28224, while the sum is 37.

The square root of 71638471 is about 8463.9512640374. The cubic root of 71638471 is about 415.3192897754.

The spelling of 71638471 in words is "seventy-one million, six hundred thirty-eight thousand, four hundred seventy-one".