71945869 has 2 divisors, whose sum is σ = 71945870. Its totient is φ = 71945868.

The previous prime is 71945851. The next prime is 71945891. The reversal of 71945869 is 96854917.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61622500 + 10323369 = 7850^2 + 3213^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71945869 is a prime.

It is a super-2 number, since 2×71945869² = 10352416132330322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71945569) 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, 35972934 + 35972935.

It is an arithmetic number, because the mean of its divisors is an integer number (35972935).

Almost surely, 2^71945869 is an apocalyptic number.

It is an amenable number.

71945869 is a deficient number, since it is larger than the sum of its proper divisors (1).

71945869 is an equidigital number, since it uses as much as digits as its factorization.

71945869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 71945869 is about 8482.0910747292. The cubic root of 71945869 is about 415.9124819745.

The spelling of 71945869 in words is "seventy-one million, nine hundred forty-five thousand, eight hundred sixty-nine".