1988857 has 4 divisors (see below), whose sum is σ = 2141860. Its totient is φ = 1835856.

The previous prime is 1988851. The next prime is 1988887. The reversal of 1988857 is 7588891.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 95481 + 1893376 = 309^2 + 1376^2 .

It is a cyclic number.

It is not a de Polignac number, because 1988857 - 2⁷ = 1988729 is a prime.

It is a Duffinian number.

1988857 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1988851) 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, 76482 + ... + 76507.

It is an arithmetic number, because the mean of its divisors is an integer number (535465).

2^1988857 is an apocalyptic number.

It is an amenable number.

1988857 is a deficient number, since it is larger than the sum of its proper divisors (153003).

1988857 is a wasteful number, since it uses less digits than its factorization.

1988857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153002.

The product of its digits is 161280, while the sum is 46.

The square root of 1988857 is about 1410.2684141680. The cubic root of 1988857 is about 125.7576807464.

The spelling of 1988857 in words is "one million, nine hundred eighty-eight thousand, eight hundred fifty-seven".