840057 has 8 divisors (see below), whose sum is σ = 1130976. Its totient is φ = 554592.

The previous prime is 840053. The next prime is 840061. The reversal of 840057 is 750048.

It is an interprime number because it is at equal distance from previous prime (840053) and next prime (840061).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 840057 - 2² = 840053 is a prime.

840057 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (840053) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 988 + ... + 1629.

It is an arithmetic number, because the mean of its divisors is an integer number (141372).

2⁸⁴⁰⁰⁵⁷ is an apocalyptic number.

It is an amenable number.

840057 is a deficient number, since it is larger than the sum of its proper divisors (290919).

840057 is a wasteful number, since it uses less digits than its factorization.

840057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2727.

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 840057 is about 916.5462345130. The cubic root of 840057 is about 94.3560137530.

Subtracting from 840057 its reverse (750048), we obtain a palindrome (90009).

The spelling of 840057 in words is "eight hundred forty thousand, fifty-seven".