642378240 has 360 divisors, whose sum is σ = 2592507060. Its totient is φ = 146571264.

The previous prime is 642378229. The next prime is 642378241. The reversal of 642378240 is 42873246.

642378240 is a `hidden beast` number, since 6 + 42 + 378 + 240 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 601622784 + 40755456 = 24528^2 + 6384^2 .

It is a tau number, because it is divible by the number of its divisors (360).

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

It is a junction number, because it is equal to n+sod(n) for n = 642378195 and 642378204.

It is not an unprimeable number, because it can be changed into a prime (642378241) 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 35 ways as a sum of consecutive naturals, for example, 1128676 + ... + 1129244.

Almost surely, 2^642378240 is an apocalyptic number.

642378240 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 642378240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1296253530).

642378240 is an abundant number, since it is smaller than the sum of its proper divisors (1950128820).

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

642378240 is a wasteful number, since it uses less digits than its factorization.

642378240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612 (or 586 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The square root of 642378240 is about 25345.1817906284. The cubic root of 642378240 is about 862.8400070946.

The spelling of 642378240 in words is "six hundred forty-two million, three hundred seventy-eight thousand, two hundred forty".