71381971 has 2 divisors, whose sum is σ = 71381972. Its totient is φ = 71381970.

The previous prime is 71381953. The next prime is 71381977. The reversal of 71381971 is 17918317.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 71381971 - 2¹⁵ = 71349203 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71381971.

It is not a weakly prime, because it can be changed into another prime (71381977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35690985 + 35690986.

It is an arithmetic number, because the mean of its divisors is an integer number (35690986).

Almost surely, 2^71381971 is an apocalyptic number.

71381971 is a deficient number, since it is larger than the sum of its proper divisors (1).

71381971 is an equidigital number, since it uses as much as digits as its factorization.

71381971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10584, while the sum is 37.

The square root of 71381971 is about 8448.7851789473. The cubic root of 71381971 is about 414.8230164188.

The spelling of 71381971 in words is "seventy-one million, three hundred eighty-one thousand, nine hundred seventy-one".