1285109280 has 576 divisors, whose sum is σ = 5646775680. Its totient is φ = 270563328.

The previous prime is 1285109263. The next prime is 1285109321. The reversal of 1285109280 is 829015821.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2751607 + ... + 2752073.

It is an arithmetic number, because the mean of its divisors is an integer number (9803430).

Almost surely, 2^1285109280 is an apocalyptic number.

1285109280 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 1285109280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2823387840).

1285109280 is an abundant number, since it is smaller than the sum of its proper divisors (4361666400).

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

1285109280 is a wasteful number, since it uses less digits than its factorization.

1285109280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 518 (or 497 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 1285109280 is about 35848.4208857238. The cubic root of 1285109280 is about 1087.2097870070.

The spelling of 1285109280 in words is "one billion, two hundred eighty-five million, one hundred nine thousand, two hundred eighty".