399787 has 2 divisors, whose sum is σ = 399788. Its totient is φ = 399786.

The previous prime is 399781. The next prime is 399793. The reversal of 399787 is 787993.

It is a balanced prime because it is at equal distance from previous prime (399781) and next prime (399793).

It is an emirp because it is prime and its reverse (787993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 399787 - 2¹⁵ = 367019 is a prime.

It is not a weakly prime, because it can be changed into another prime (399781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199893 + 199894.

It is an arithmetic number, because the mean of its divisors is an integer number (199894).

2³⁹⁹⁷⁸⁷ is an apocalyptic number.

399787 is a deficient number, since it is larger than the sum of its proper divisors (1).

399787 is an equidigital number, since it uses as much as digits as its factorization.

399787 is an evil number, because the sum of its binary digits is even.

The product of its digits is 95256, while the sum is 43.

The square root of 399787 is about 632.2871183252. The cubic root of 399787 is about 73.6675493389.

The spelling of 399787 in words is "three hundred ninety-nine thousand, seven hundred eighty-seven".