642646040 has 64 divisors (see below), whose sum is σ = 1495756800. Its totient is φ = 248347008.

The previous prime is 642646001. The next prime is 642646057. The reversal of 642646040 is 40646246.

It is a junction number, because it is equal to n+sod(n) for n = 642645988 and 642646006.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 146357 + ... + 150683.

It is an arithmetic number, because the mean of its divisors is an integer number (23371200).

Almost surely, 2^642646040 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 642646040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747878400).

642646040 is an abundant number, since it is smaller than the sum of its proper divisors (853110760).

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

642646040 is a wasteful number, since it uses less digits than its factorization.

642646040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4464 (or 4460 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

The square root of 642646040 is about 25350.4642955509. The cubic root of 642646040 is about 862.9598930834.

The spelling of 642646040 in words is "six hundred forty-two million, six hundred forty-six thousand, forty".