642428280 has 128 divisors (see below), whose sum is σ = 2306203200. Its totient is φ = 158132736.

The previous prime is 642428273. The next prime is 642428333. The reversal of 642428280 is 82824246.

It is a happy number.

642428280 is a `hidden beast` number, since 642 + 4 + 2 + 8 + 2 + 8 + 0 = 666.

642428280 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8839 + ... + 36918.

Almost surely, 2^642428280 is an apocalyptic number.

642428280 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 642428280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1153101600).

642428280 is an abundant number, since it is smaller than the sum of its proper divisors (1663774920).

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

642428280 is a wasteful number, since it uses less digits than its factorization.

642428280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45790 (or 45780 counting only the distinct ones).

The product of its (nonzero) digits is 49152, while the sum is 36.

The square root of 642428280 is about 25346.1689412818. The cubic root of 642428280 is about 862.8624110254.

The spelling of 642428280 in words is "six hundred forty-two million, four hundred twenty-eight thousand, two hundred eighty".