71685091 has 2 divisors, whose sum is σ = 71685092. Its totient is φ = 71685090.

The previous prime is 71685083. The next prime is 71685127. The reversal of 71685091 is 19058617.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71685091 - 2³ = 71685083 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71685091.

It is not a weakly prime, because it can be changed into another prime (71685041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35842545 + 35842546.

It is an arithmetic number, because the mean of its divisors is an integer number (35842546).

Almost surely, 2^71685091 is an apocalyptic number.

71685091 is a deficient number, since it is larger than the sum of its proper divisors (1).

71685091 is an equidigital number, since it uses as much as digits as its factorization.

71685091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 71685091 is about 8466.7048489953. The cubic root of 71685091 is about 415.4093623600.

The spelling of 71685091 in words is "seventy-one million, six hundred eighty-five thousand, ninety-one".