1399666 has 8 divisors (see below), whose sum is σ = 2104560. Its totient is φ = 698148.

The previous prime is 1399663. The next prime is 1399679. The reversal of 1399666 is 6669931.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a nialpdrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (1399663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1005 + ... + 1951.

It is an arithmetic number, because the mean of its divisors is an integer number (263070).

2^1399666 is an apocalyptic number.

1399666 is a deficient number, since it is larger than the sum of its proper divisors (704894).

1399666 is an equidigital number, since it uses as much as digits as its factorization.

1399666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1688.

The product of its digits is 52488, while the sum is 40.

The square root of 1399666 is about 1183.0748074403. The cubic root of 1399666 is about 111.8599972599.

The spelling of 1399666 in words is "one million, three hundred ninety-nine thousand, six hundred sixty-six".