1285333920 has 288 divisors, whose sum is σ = 4900476672. Its totient is φ = 316265472.

The previous prime is 1285333913. The next prime is 1285333961. The reversal of 1285333920 is 293335821.

It is a tau number, because it is divible by the number of its divisors (288).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 504169 + ... + 506711.

It is an arithmetic number, because the mean of its divisors is an integer number (17015544).

Almost surely, 2^1285333920 is an apocalyptic number.

1285333920 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 1285333920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2450238336).

1285333920 is an abundant number, since it is smaller than the sum of its proper divisors (3615142752).

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

1285333920 is a wasteful number, since it uses less digits than its factorization.

1285333920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2586 (or 2566 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 1285333920 is about 35851.5539412171. The cubic root of 1285333920 is about 1087.2731322236.

The spelling of 1285333920 in words is "one billion, two hundred eighty-five million, three hundred thirty-three thousand, nine hundred twenty".