71987 has 2 divisors, whose sum is σ = 71988. Its totient is φ = 71986.

The previous prime is 71983. The next prime is 71993. The reversal of 71987 is 78917.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71987 - 2² = 71983 is a prime.

It is a Chen prime.

It is a plaindrome in base 12.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 71987.

It is not a weakly prime, because it can be changed into another prime (71983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35993 + 35994.

It is an arithmetic number, because the mean of its divisors is an integer number (35994).

2⁷¹⁹⁸⁷ is an apocalyptic number.

71987 is a deficient number, since it is larger than the sum of its proper divisors (1).

71987 is an equidigital number, since it uses as much as digits as its factorization.

71987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3528, while the sum is 32.

The square root of 71987 is about 268.3039321367. The cubic root of 71987 is about 41.5991725057.

The spelling of 71987 in words is "seventy-one thousand, nine hundred eighty-seven".