71999 has 2 divisors, whose sum is σ = 72000. Its totient is φ = 71998.

The previous prime is 71993. The next prime is 72019. The reversal of 71999 is 99917.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 71999 - 2⁴ = 71983 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

71999 is a modest number, since divided by 999 gives 71 as remainder.

It is a plaindrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (71993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35999 + 36000.

It is an arithmetic number, because the mean of its divisors is an integer number (36000).

2⁷¹⁹⁹⁹ is an apocalyptic number.

71999 is a deficient number, since it is larger than the sum of its proper divisors (1).

71999 is an equidigital number, since it uses as much as digits as its factorization.

71999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5103, while the sum is 35.

The square root of 71999 is about 268.3262939035. The cubic root of 71999 is about 41.6014838598.

It can be divided in two parts, 719 and 99, that added together give a palindrome (818).

The spelling of 71999 in words is "seventy-one thousand, nine hundred ninety-nine".