1656745 has 4 divisors (see below), whose sum is σ = 1988100. Its totient is φ = 1325392.

The previous prime is 1656719. The next prime is 1656761. The reversal of 1656745 is 5476561.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5476561 = 313 ⋅17497.

It can be written as a sum of positive squares in 2 ways, for example, as 318096 + 1338649 = 564^2 + 1157^2 .

It is a cyclic number.

It is not a de Polignac number, because 1656745 - 2⁷ = 1656617 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1656745.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 165670 + ... + 165679.

It is an arithmetic number, because the mean of its divisors is an integer number (497025).

2^1656745 is an apocalyptic number.

It is an amenable number.

1656745 is a deficient number, since it is larger than the sum of its proper divisors (331355).

1656745 is an equidigital number, since it uses as much as digits as its factorization.

1656745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331354.

The product of its digits is 25200, while the sum is 34.

The square root of 1656745 is about 1287.1460678571. The cubic root of 1656745 is about 118.3273730164.

It can be divided in two parts, 1656 and 745, that added together give a 4-th power (2401 = 7⁴).

The spelling of 1656745 in words is "one million, six hundred fifty-six thousand, seven hundred forty-five".