642783 has 8 divisors (see below), whose sum is σ = 862848. Its totient is φ = 425624.

The previous prime is 642779. The next prime is 642791. The reversal of 642783 is 387246.

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

It is a cyclic number.

It is not a de Polignac number, because 642783 - 2² = 642779 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 642783.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642683) 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, 141 + ... + 1142.

It is an arithmetic number, because the mean of its divisors is an integer number (107856).

2⁶⁴²⁷⁸³ is an apocalyptic number.

642783 is a deficient number, since it is larger than the sum of its proper divisors (220065).

642783 is a wasteful number, since it uses less digits than its factorization.

642783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1453.

The product of its digits is 8064, while the sum is 30.

The square root of 642783 is about 801.7374882092. The cubic root of 642783 is about 86.3021193076.

The spelling of 642783 in words is "six hundred forty-two thousand, seven hundred eighty-three".