642872 has 32 divisors (see below), whose sum is σ = 1328400. Its totient is φ = 290304.

The previous prime is 642871. The next prime is 642877. The reversal of 642872 is 278246.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a nialpdrome in base 15.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642872.

It is not an unprimeable number, because it can be changed into a prime (642871) 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, 3863 + ... + 4025.

2⁶⁴²⁸⁷² is an apocalyptic number.

It is an amenable number.

642872 is an abundant number, since it is smaller than the sum of its proper divisors (685528).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642872 is a wasteful number, since it uses less digits than its factorization.

642872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 215 (or 211 counting only the distinct ones).

The product of its digits is 5376, while the sum is 29.

The square root of 642872 is about 801.7929907401. The cubic root of 642872 is about 86.3061022661.

The spelling of 642872 in words is "six hundred forty-two thousand, eight hundred seventy-two".