1690993 has 2 divisors, whose sum is σ = 1690994. Its totient is φ = 1690992.

The previous prime is 1690967. The next prime is 1691003. The reversal of 1690993 is 3990961.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1272384 + 418609 = 1128^2 + 647^2 .

It is a cyclic number.

It is not a de Polignac number, because 1690993 - 2¹³ = 1682801 is a prime.

It is not a weakly prime, because it can be changed into another prime (1690933) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845496 + 845497.

It is an arithmetic number, because the mean of its divisors is an integer number (845497).

2^1690993 is an apocalyptic number.

It is an amenable number.

1690993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1690993 is an equidigital number, since it uses as much as digits as its factorization.

1690993 is an evil number, because the sum of its binary digits is even.

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

The square root of 1690993 is about 1300.3818669914. The cubic root of 1690993 is about 119.1371673494.

Subtracting 1690993 from its reverse (3990961), we obtain a cube (2299968 = 132³).

The spelling of 1690993 in words is "one million, six hundred ninety thousand, nine hundred ninety-three".