1287785280 has 56 divisors (see below), whose sum is σ = 4088721312. Its totient is φ = 343409152.

The previous prime is 1287785251. The next prime is 1287785321. The reversal of 1287785280 is 825877821.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 669762 + ... + 671681.

Almost surely, 2^1287785280 is an apocalyptic number.

1287785280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1287785280 is an abundant number, since it is smaller than the sum of its proper divisors (2800936032).

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

1287785280 is a wasteful number, since it uses less digits than its factorization.

1287785280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1341463 (or 1341453 counting only the distinct ones).

The product of its (nonzero) digits is 501760, while the sum is 48.

The square root of 1287785280 is about 35885.7252957217. The cubic root of 1287785280 is about 1087.9639009072.

The spelling of 1287785280 in words is "one billion, two hundred eighty-seven million, seven hundred eighty-five thousand, two hundred eighty".