1284661440 has 336 divisors, whose sum is σ = 4928433120. Its totient is φ = 305233920.

The previous prime is 1284661397. The next prime is 1284661447. The reversal of 1284661440 is 441664821.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 1284661395 and 1284661404.

It is not an unprimeable number, because it can be changed into a prime (1284661447) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 929550 + ... + 930930.

Almost surely, 2^1284661440 is an apocalyptic number.

1284661440 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 1284661440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2464216560).

1284661440 is an abundant number, since it is smaller than the sum of its proper divisors (3643771680).

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

1284661440 is a wasteful number, since it uses less digits than its factorization.

1284661440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1440 (or 1427 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 1284661440 is about 35842.1740412046. The cubic root of 1284661440 is about 1087.0834806018.

The spelling of 1284661440 in words is "one billion, two hundred eighty-four million, six hundred sixty-one thousand, four hundred forty".