1428189840 has 640 divisors, whose sum is σ = 6353879040. Its totient is φ = 286156800.

The previous prime is 1428189811. The next prime is 1428189857. The reversal of 1428189840 is 489818241.

1428189840 is a `hidden beast` number, since 1 + 428 + 189 + 8 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5155782 + ... + 5156058.

It is an arithmetic number, because the mean of its divisors is an integer number (9927936).

Almost surely, 2^1428189840 is an apocalyptic number.

1428189840 is a gapful number since it is divisible by the number (10) 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 1428189840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3176939520).

1428189840 is an abundant number, since it is smaller than the sum of its proper divisors (4925689200).

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

1428189840 is a wasteful number, since it uses less digits than its factorization.

1428189840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348 (or 336 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 45.

The square root of 1428189840 is about 37791.3990214705. The cubic root of 1428189840 is about 1126.1475934058.

The spelling of 1428189840 in words is "one billion, four hundred twenty-eight million, one hundred eighty-nine thousand, eight hundred forty".