1278778860 has 48 divisors (see below), whose sum is σ = 3978424800. Its totient is φ = 341007552.

The previous prime is 1278778843. The next prime is 1278778871. The reversal of 1278778860 is 688778721.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 1278778797 and 1278778806.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1183515 + ... + 1184594.

It is an arithmetic number, because the mean of its divisors is an integer number (82883850).

Almost surely, 2^1278778860 is an apocalyptic number.

1278778860 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1278778860 is an abundant number, since it is smaller than the sum of its proper divisors (2699645940).

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

1278778860 is a wasteful number, since it uses less digits than its factorization.

1278778860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2368127 (or 2368119 counting only the distinct ones).

The product of its (nonzero) digits is 2107392, while the sum is 54.

The square root of 1278778860 is about 35760.0176174453. The cubic root of 1278778860 is about 1085.4216572032.

The spelling of 1278778860 in words is "one billion, two hundred seventy-eight million, seven hundred seventy-eight thousand, eight hundred sixty".