642867 has 8 divisors (see below), whose sum is σ = 860880. Its totient is φ = 426720.

The previous prime is 642853. The next prime is 642869. The reversal of 642867 is 768246.

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

It is not a de Polignac number, because 642867 - 2⁷ = 642739 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642867.

It is not an unprimeable number, because it can be changed into a prime (642869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1009 + ... + 1517.

It is an arithmetic number, because the mean of its divisors is an integer number (107610).

2⁶⁴²⁸⁶⁷ is an apocalyptic number.

642867 is a deficient number, since it is larger than the sum of its proper divisors (218013).

642867 is a wasteful number, since it uses less digits than its factorization.

642867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 933.

The product of its digits is 16128, while the sum is 33.

The square root of 642867 is about 801.7898727223. The cubic root of 642867 is about 86.3058785141.

The spelling of 642867 in words is "six hundred forty-two thousand, eight hundred sixty-seven".