840172 has 24 divisors (see below), whose sum is σ = 1552320. Its totient is φ = 397440.

The previous prime is 840163. The next prime is 840179. The reversal of 840172 is 271048.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (840179) 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, 7654 + ... + 7762.

It is an arithmetic number, because the mean of its divisors is an integer number (64680).

2⁸⁴⁰¹⁷² is an apocalyptic number.

840172 is a gapful number since it is divisible by the number (82) formed by its first and last digit.

It is an amenable number.

840172 is a deficient number, since it is larger than the sum of its proper divisors (712148).

840172 is a wasteful number, since it uses less digits than its factorization.

840172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201 (or 199 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 840172 is about 916.6089678811. The cubic root of 840172 is about 94.3603191935.

The spelling of 840172 in words is "eight hundred forty thousand, one hundred seventy-two".