1278115155 has 48 divisors (see below), whose sum is σ = 2246602176. Its totient is φ = 672122880.

The previous prime is 1278115141. The next prime is 1278115169. The reversal of 1278115155 is 5515118721.

1278115155 is a `hidden beast` number, since 127 + 8 + 11 + 515 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (1278115141) and next prime (1278115169).

It is not a de Polignac number, because 1278115155 - 2¹¹ = 1278113107 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1450315 + ... + 1451195.

It is an arithmetic number, because the mean of its divisors is an integer number (46804212).

Almost surely, 2^1278115155 is an apocalyptic number.

1278115155 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1278115155 is a deficient number, since it is larger than the sum of its proper divisors (968487021).

1278115155 is a wasteful number, since it uses less digits than its factorization.

1278115155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1308 (or 1305 counting only the distinct ones).

The product of its digits is 14000, while the sum is 36.

The square root of 1278115155 is about 35750.7364259815. The cubic root of 1278115155 is about 1085.2338414486.

The spelling of 1278115155 in words is "one billion, two hundred seventy-eight million, one hundred fifteen thousand, one hundred fifty-five".