642320280 has 320 divisors, whose sum is σ = 2497904640. Its totient is φ = 145006848.

The previous prime is 642320221. The next prime is 642320351. The reversal of 642320280 is 82023246.

642320280 is a `hidden beast` number, since 64 + 2 + 320 + 280 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2880249 + ... + 2880471.

It is an arithmetic number, because the mean of its divisors is an integer number (7805952).

Almost surely, 2^642320280 is an apocalyptic number.

642320280 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 642320280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1248952320).

642320280 is an abundant number, since it is smaller than the sum of its proper divisors (1855584360).

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

642320280 is a wasteful number, since it uses less digits than its factorization.

642320280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 642320280 is about 25344.0383522437. The cubic root of 642320280 is about 862.8140557636.

The spelling of 642320280 in words is "six hundred forty-two million, three hundred twenty thousand, two hundred eighty".