642624929856 has 448 divisors, whose sum is σ = 2374666076160. Its totient is φ = 165875558400.

The previous prime is 642624929747. The next prime is 642624929861. The reversal of 642624929856 is 658929426246.

642624929856 is a `hidden beast` number, since 6 + 4 + 2 + 6 + 2 + 492 + 98 + 56 = 666.

It is a tau number, because it is divible by the number of its divisors (448).

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

It is a junction number, because it is equal to n+sod(n) for n = 642624929793 and 642624929802.

It is an unprimeable number.

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, 7347181 + ... + 7434131.

It is an arithmetic number, because the mean of its divisors is an integer number (5300593920).

Almost surely, 2^642624929856 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 642624929856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1187333038080).

642624929856 is an abundant number, since it is smaller than the sum of its proper divisors (1732041146304).

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

642624929856 is a wasteful number, since it uses less digits than its factorization.

642624929856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87039 (or 87023 counting only the distinct ones).

The product of its digits is 89579520, while the sum is 63.

The spelling of 642624929856 in words is "six hundred forty-two billion, six hundred twenty-four million, nine hundred twenty-nine thousand, eight hundred fifty-six".