642543720 has 256 divisors, whose sum is σ = 2455488000. Its totient is φ = 130830336.

The previous prime is 642543641. The next prime is 642543731. The reversal of 642543720 is 27345246.

It is a super-2 number, since 2×642543720² = 825724864222876800, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 315666 + ... + 317694.

It is an arithmetic number, because the mean of its divisors is an integer number (9591750).

Almost surely, 2^642543720 is an apocalyptic number.

642543720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642543720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1227744000).

642543720 is an abundant number, since it is smaller than the sum of its proper divisors (1812944280).

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

642543720 is a wasteful number, since it uses less digits than its factorization.

642543720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2092 (or 2088 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 33.

The square root of 642543720 is about 25348.4461062212. The cubic root of 642543720 is about 862.9140914355.

Adding to 642543720 its reverse (27345246), we get a palindrome (669888966).

The spelling of 642543720 in words is "six hundred forty-two million, five hundred forty-three thousand, seven hundred twenty".