1897897 has 4 divisors (see below), whose sum is σ = 2009556. Its totient is φ = 1786240.

The previous prime is 1897871. The next prime is 1897939. The reversal of 1897897 is 7987981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7987981 = 43 ⋅185767.

It can be written as a sum of positive squares in 2 ways, for example, as 1058841 + 839056 = 1029^2 + 916^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1897897 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1897897.

It is not an unprimeable number, because it can be changed into a prime (1897807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55804 + ... + 55837.

It is an arithmetic number, because the mean of its divisors is an integer number (502389).

2^1897897 is an apocalyptic number.

1897897 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

1897897 is a deficient number, since it is larger than the sum of its proper divisors (111659).

1897897 is a wasteful number, since it uses less digits than its factorization.

1897897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111658.

The product of its digits is 254016, while the sum is 49.

The square root of 1897897 is about 1377.6418257298. The cubic root of 1897897 is about 123.8105196618.

The spelling of 1897897 in words is "one million, eight hundred ninety-seven thousand, eight hundred ninety-seven".