1681057 has 4 divisors (see below), whose sum is σ = 1921216. Its totient is φ = 1440900.

The previous prime is 1681033. The next prime is 1681061. The reversal of 1681057 is 7501861.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7501861 = 37 ⋅202753.

It is a cyclic number.

It is not a de Polignac number, because 1681057 - 2⁷ = 1680929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1681007) 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, 120069 + ... + 120082.

It is an arithmetic number, because the mean of its divisors is an integer number (480304).

2^1681057 is an apocalyptic number.

It is an amenable number.

1681057 is a deficient number, since it is larger than the sum of its proper divisors (240159).

1681057 is an equidigital number, since it uses as much as digits as its factorization.

1681057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240158.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 1681057 is about 1296.5558221689. Note that the first 3 decimals coincide. The cubic root of 1681057 is about 118.9033652788.

It can be divided in two parts, 168 and 1057, that added together give a triangular number (1225 = T₄₉).

The spelling of 1681057 in words is "one million, six hundred eighty-one thousand, fifty-seven".