1391866 has 16 divisors (see below), whose sum is σ = 2451456. Its totient is φ = 580176.

The previous prime is 1391861. The next prime is 1391893. The reversal of 1391866 is 6681931.

1391866 is nontrivially palindromic in base 6.

It is not an unprimeable number, because it can be changed into a prime (1391861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 826 + ... + 1861.

It is an arithmetic number, because the mean of its divisors is an integer number (153216).

2^1391866 is an apocalyptic number.

1391866 is a deficient number, since it is larger than the sum of its proper divisors (1059590).

1391866 is a wasteful number, since it uses less digits than its factorization.

1391866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2733.

The product of its digits is 7776, while the sum is 34.

The square root of 1391866 is about 1179.7737071151. The cubic root of 1391866 is about 111.6518205059.

The spelling of 1391866 in words is "one million, three hundred ninety-one thousand, eight hundred sixty-six".