1278701855209 has 9 divisors (see below), whose sum is σ = 1324349440453. Its totient is φ = 1234577025472.

The previous prime is 1278701855149. The next prime is 1278701855273. The reversal of 1278701855209 is 9025581078721.

It is a happy number.

The square root of 1278701855209 is 1130797.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 59382379225 + 1219319475984 = 243685^2 + 1104228^2 .

It is not a de Polignac number, because 1278701855209 - 2⁹ = 1278701854697 is a prime.

It is a super-3 number, since 3×1278701855209³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1278701855209.

It is not an unprimeable number, because it can be changed into a prime (1278701825209) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 32773617 + ... + 32812609.

Almost surely, 2^{1278701855209} is an apocalyptic number.

1278701855209 is the 1130797-th square number.

1278701855209 is the 565399-th centered octagonal number.

It is an amenable number.

1278701855209 is a deficient number, since it is larger than the sum of its proper divisors (45647585244).

1278701855209 is an frugal number, since it uses more digits than its factorization.

1278701855209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78044 (or 39022 counting only the distinct ones).

The product of its (nonzero) digits is 2822400, while the sum is 55.

The spelling of 1278701855209 in words is "one trillion, two hundred seventy-eight billion, seven hundred one million, eight hundred fifty-five thousand, two hundred nine".