642028860 has 144 divisors (see below), whose sum is σ = 2154926592. Its totient is φ = 153417600.

The previous prime is 642028859. The next prime is 642028927. The reversal of 642028860 is 68820246.

642028860 is a `hidden beast` number, since 642 + 0 + 2 + 8 + 8 + 6 + 0 = 666.

642028860 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 47 ways as a sum of consecutive naturals, for example, 138297 + ... + 142863.

It is an arithmetic number, because the mean of its divisors is an integer number (14964768).

Almost surely, 2^642028860 is an apocalyptic number.

642028860 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642028860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1077463296).

642028860 is an abundant number, since it is smaller than the sum of its proper divisors (1512897732).

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

642028860 is a wasteful number, since it uses less digits than its factorization.

642028860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4664 (or 4659 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 642028860 is about 25338.2884189126. The cubic root of 642028860 is about 862.6835500976.

The spelling of 642028860 in words is "six hundred forty-two million, twenty-eight thousand, eight hundred sixty".