71970181 has 2 divisors, whose sum is σ = 71970182. Its totient is φ = 71970180.

The previous prime is 71970167. The next prime is 71970203. The reversal of 71970181 is 18107917.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71673156 + 297025 = 8466^2 + 545^2 .

It is an emirp because it is prime and its reverse (18107917) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 71970181 - 2¹⁹ = 71445893 is a prime.

It is a super-2 number, since 2×71970181² = 10359413906345522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71970121) 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, 35985090 + 35985091.

It is an arithmetic number, because the mean of its divisors is an integer number (35985091).

Almost surely, 2^71970181 is an apocalyptic number.

It is an amenable number.

71970181 is a deficient number, since it is larger than the sum of its proper divisors (1).

71970181 is an equidigital number, since it uses as much as digits as its factorization.

71970181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3528, while the sum is 34.

The square root of 71970181 is about 8483.5240908481. The cubic root of 71970181 is about 415.9593251805.

The spelling of 71970181 in words is "seventy-one million, nine hundred seventy thousand, one hundred eighty-one".