642912500 has 72 divisors (see below), whose sum is σ = 1480842720. Its totient is φ = 243540000.

The previous prime is 642912449. The next prime is 642912547. The reversal of 642912500 is 5219246.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 236147 + ... + 238853.

It is an arithmetic number, because the mean of its divisors is an integer number (20567260).

Almost surely, 2^642912500 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 642912500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (740421360).

642912500 is an abundant number, since it is smaller than the sum of its proper divisors (837930220).

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

642912500 is a wasteful number, since it uses less digits than its factorization.

642912500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2755 (or 2733 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 642912500 is about 25355.7192759346. The cubic root of 642912500 is about 863.0791461432.

The spelling of 642912500 in words is "six hundred forty-two million, nine hundred twelve thousand, five hundred".