1680993 has 10 divisors (see below), whose sum is σ = 2511234. Its totient is φ = 1120608.

The previous prime is 1680983. The next prime is 1681003. The reversal of 1680993 is 3990861.

It is an interprime number because it is at equal distance from previous prime (1680983) and next prime (1681003).

It can be written as a sum of positive squares in only one way, i.e., 1306449 + 374544 = 1143^2 + 612^2 .

It is not a de Polignac number, because 1680993 - 2⁵ = 1680961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1680983) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 10296 + ... + 10457.

2^1680993 is an apocalyptic number.

It is an amenable number.

1680993 is a deficient number, since it is larger than the sum of its proper divisors (830241).

1680993 is an equidigital number, since it uses as much as digits as its factorization.

1680993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20765 (or 20756 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 1680993 is about 1296.5311411609. The cubic root of 1680993 is about 118.9018563250.

The spelling of 1680993 in words is "one million, six hundred eighty thousand, nine hundred ninety-three".