642748257648 has 320 divisors, whose sum is σ = 2154612096000. Its totient is φ = 179645506560.

The previous prime is 642748257617. The next prime is 642748257649. The reversal of 642748257648 is 846752847246.

It is a happy number.

642748257648 is a `hidden beast` number, since 6 + 42 + 7 + 482 + 5 + 76 + 48 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642748257649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 55929183 + ... + 55940673.

It is an arithmetic number, because the mean of its divisors is an integer number (6733162800).

Almost surely, 2^642748257648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642748257648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1077306048000).

642748257648 is an abundant number, since it is smaller than the sum of its proper divisors (1511863838352).

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

642748257648 is a wasteful number, since it uses less digits than its factorization.

642748257648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11917 (or 11905 counting only the distinct ones).

The product of its digits is 144506880, while the sum is 63.

The spelling of 642748257648 in words is "six hundred forty-two billion, seven hundred forty-eight million, two hundred fifty-seven thousand, six hundred forty-eight".