1298780663780 has 24 divisors (see below), whose sum is σ = 2729013292152. Its totient is φ = 519212475392.

The previous prime is 1298780663749. The next prime is 1298780663783. The reversal of 1298780663780 is 873660878921.

It can be written as a sum of positive squares in 4 ways, for example, as 15304658944 + 1283476004836 = 123712^2 + 1132906^2 .

It is not an unprimeable number, because it can be changed into a prime (1298780663783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18701357 + ... + 18770676.

It is an arithmetic number, because the mean of its divisors is an integer number (113708887173).

Almost surely, 2^{1298780663780} is an apocalyptic number.

1298780663780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1298780663780 is an abundant number, since it is smaller than the sum of its proper divisors (1430232628372).

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

1298780663780 is a wasteful number, since it uses less digits than its factorization.

1298780663780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37473775 (or 37473773 counting only the distinct ones).

The product of its (nonzero) digits is 48771072, while the sum is 65.

The spelling of 1298780663780 in words is "one trillion, two hundred ninety-eight billion, seven hundred eighty million, six hundred sixty-three thousand, seven hundred eighty".