642563320 has 128 divisors (see below), whose sum is σ = 1703669760. Its totient is φ = 213557760.

The previous prime is 642563279. The next prime is 642563329. The reversal of 642563320 is 23365246.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642563329) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2065965 + ... + 2066275.

It is an arithmetic number, because the mean of its divisors is an integer number (13309920).

Almost surely, 2^642563320 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 642563320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (851834880).

642563320 is an abundant number, since it is smaller than the sum of its proper divisors (1061106440).

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

642563320 is a wasteful number, since it uses less digits than its factorization.

642563320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 533 (or 529 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 31.

The square root of 642563320 is about 25348.8327147425. The cubic root of 642563320 is about 862.9228653880.

It can be divided in two parts, 64256 and 3320, that added together give a palindrome (67576).

The spelling of 642563320 in words is "six hundred forty-two million, five hundred sixty-three thousand, three hundred twenty".