1281780750920 has 16 divisors (see below), whose sum is σ = 2884006689660. Its totient is φ = 512712300352.

The previous prime is 1281780750869. The next prime is 1281780750949. The reversal of 1281780750920 is 290570871821.

It can be written as a sum of positive squares in 2 ways, for example, as 1253132480356 + 28648270564 = 1119434^2 + 169258^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16022259347 + ... + 16022259426.

Almost surely, 2^{1281780750920} is an apocalyptic number.

1281780750920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1281780750920 is an abundant number, since it is smaller than the sum of its proper divisors (1602225938740).

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

1281780750920 is a wasteful number, since it uses less digits than its factorization.

1281780750920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32044518784 (or 32044518780 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 50.

The spelling of 1281780750920 in words is "one trillion, two hundred eighty-one billion, seven hundred eighty million, seven hundred fifty thousand, nine hundred twenty".