642442364928 has 1728 divisors, whose sum is σ = 2542393526400. Its totient is φ = 159411732480.

The previous prime is 642442364917. The next prime is 642442364929. The reversal of 642442364928 is 829463244246.

It is a happy number.

642442364928 is a `hidden beast` number, since 64 + 24 + 42 + 36 + 492 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (1728).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (642442364929) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 10531842018 + ... + 10531842078.

It is an arithmetic number, because the mean of its divisors is an integer number (1471292550).

Almost surely, 2^642442364928 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 642442364928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1271196763200).

642442364928 is an abundant number, since it is smaller than the sum of its proper divisors (1899951161472).

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

642442364928 is a wasteful number, since it uses less digits than its factorization.

642442364928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155 (or 109 counting only the distinct ones).

The product of its digits is 15925248, while the sum is 54.

The spelling of 642442364928 in words is "six hundred forty-two billion, four hundred forty-two million, three hundred sixty-four thousand, nine hundred twenty-eight".