1680457 has 2 divisors, whose sum is σ = 1680458. Its totient is φ = 1680456.

The previous prime is 1680439. The next prime is 1680461. The reversal of 1680457 is 7540861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1679616 + 841 = 1296^2 + 29^2 .

It is an emirp because it is prime and its reverse (7540861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1680457 - 2¹¹ = 1678409 is a prime.

It is a nialpdrome in base 8.

It is not a weakly prime, because it can be changed into another prime (1680407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840228 + 840229.

It is an arithmetic number, because the mean of its divisors is an integer number (840229).

2^1680457 is an apocalyptic number.

It is an amenable number.

1680457 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680457 is an equidigital number, since it uses as much as digits as its factorization.

1680457 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 1680457 is about 1296.3244192717. The cubic root of 1680457 is about 118.8892173333.

It can be divided in two parts, 16804 and 57, that added together give a palindrome (16861).

The spelling of 1680457 in words is "one million, six hundred eighty thousand, four hundred fifty-seven".