1690399 has 6 divisors (see below), whose sum is σ = 1747680. Its totient is φ = 1634940.

The previous prime is 1690393. The next prime is 1690421. The reversal of 1690399 is 9930961.

It is not a de Polignac number, because 1690399 - 2¹³ = 1682207 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1690393) 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 5 ways as a sum of consecutive naturals, for example, 82 + ... + 1840.

It is an arithmetic number, because the mean of its divisors is an integer number (291280).

2^1690399 is an apocalyptic number.

1690399 is a deficient number, since it is larger than the sum of its proper divisors (57281).

1690399 is an equidigital number, since it uses as much as digits as its factorization.

1690399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1821 (or 1790 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 1690399 is about 1300.1534524817. The cubic root of 1690399 is about 119.1232158300.

The spelling of 1690399 in words is "one million, six hundred ninety thousand, three hundred ninety-nine".