642750 has 32 divisors (see below), whose sum is σ = 1606176. Its totient is φ = 171200.

The previous prime is 642739. The next prime is 642769. The reversal of 642750 is 57246.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 642750.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 322 + ... + 1178.

It is an arithmetic number, because the mean of its divisors is an integer number (50193).

2⁶⁴²⁷⁵⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642750, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (803088).

642750 is an abundant number, since it is smaller than the sum of its proper divisors (963426).

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

642750 is a wasteful number, since it uses less digits than its factorization.

642750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 877 (or 867 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 24.

The square root of 642750 is about 801.7169076426. The cubic root of 642750 is about 86.3006423868.

Adding to 642750 its reverse (57246), we get a palindrome (699996).

The spelling of 642750 in words is "six hundred forty-two thousand, seven hundred fifty".