1398779 has 2 divisors, whose sum is σ = 1398780. Its totient is φ = 1398778.

The previous prime is 1398773. The next prime is 1398781. The reversal of 1398779 is 9778931.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1398779 - 2⁴ = 1398763 is a prime.

Together with 1398781, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1398773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 699389 + 699390.

It is an arithmetic number, because the mean of its divisors is an integer number (699390).

2^1398779 is an apocalyptic number.

1398779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1398779 is an equidigital number, since it uses as much as digits as its factorization.

1398779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 44.

The square root of 1398779 is about 1182.6998773992. The cubic root of 1398779 is about 111.8363628633.

The spelling of 1398779 in words is "one million, three hundred ninety-eight thousand, seven hundred seventy-nine".