1280860920 has 384 divisors, whose sum is σ = 4637917440. Its totient is φ = 305233920.

The previous prime is 1280860907. The next prime is 1280860949. The reversal of 1280860920 is 290680821.

1280860920 is a `hidden beast` number, since 1 + 28 + 0 + 8 + 609 + 20 = 666.

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 95 ways as a sum of consecutive naturals, for example, 17546004 + ... + 17546076.

It is an arithmetic number, because the mean of its divisors is an integer number (12077910).

Almost surely, 2^1280860920 is an apocalyptic number.

1280860920 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 1280860920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2318958720).

1280860920 is an abundant number, since it is smaller than the sum of its proper divisors (3357056520).

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

1280860920 is a wasteful number, since it uses less digits than its factorization.

1280860920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215 (or 208 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 1280860920 is about 35789.1173403313. The cubic root of 1280860920 is about 1086.0104187924.

The spelling of 1280860920 in words is "one billion, two hundred eighty million, eight hundred sixty thousand, nine hundred twenty".