390688289 has 2 divisors, whose sum is σ = 390688290. Its totient is φ = 390688288.

The previous prime is 390688247. The next prime is 390688313. The reversal of 390688289 is 982886093.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 216237025 + 174451264 = 14705^2 + 13208^2 .

It is a cyclic number.

It is not a de Polignac number, because 390688289 - 2¹² = 390684193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 390688289.

It is not a weakly prime, because it can be changed into another prime (390688229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195344144 + 195344145.

It is an arithmetic number, because the mean of its divisors is an integer number (195344145).

Almost surely, 2^390688289 is an apocalyptic number.

It is an amenable number.

390688289 is a deficient number, since it is larger than the sum of its proper divisors (1).

390688289 is an equidigital number, since it uses as much as digits as its factorization.

390688289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1492992, while the sum is 53.

The square root of 390688289 is about 19765.8364103318. The cubic root of 390688289 is about 731.0439114951.

The spelling of 390688289 in words is "three hundred ninety million, six hundred eighty-eight thousand, two hundred eighty-nine".