1285821280 has 48 divisors (see below), whose sum is σ = 3039996960. Its totient is φ = 513948672.

The previous prime is 1285821263. The next prime is 1285821293. The reversal of 1285821280 is 821285821.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 332317 + ... + 336163.

It is an arithmetic number, because the mean of its divisors is an integer number (63333270).

Almost surely, 2^1285821280 is an apocalyptic number.

1285821280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1285821280 is an abundant number, since it is smaller than the sum of its proper divisors (1754175680).

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

1285821280 is a wasteful number, since it uses less digits than its factorization.

1285821280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5951 (or 5943 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 37.

The square root of 1285821280 is about 35858.3502130257. The cubic root of 1285821280 is about 1087.4105352923.

The spelling of 1285821280 in words is "one billion, two hundred eighty-five million, eight hundred twenty-one thousand, two hundred eighty".