1278518738540 has 48 divisors (see below), whose sum is σ = 2855238271200. Its totient is φ = 479222817792.

The previous prime is 1278518738527. The next prime is 1278518738597. The reversal of 1278518738540 is 458378158721.

It is a super-2 number, since 2×1278518738540² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1278518738540.

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, 8132510 + ... + 8288229.

It is an arithmetic number, because the mean of its divisors is an integer number (59484130650).

Almost surely, 2^{1278518738540} is an apocalyptic number.

1278518738540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1278518738540 is an abundant number, since it is smaller than the sum of its proper divisors (1576719532660).

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

1278518738540 is a wasteful number, since it uses less digits than its factorization.

1278518738540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16420994 (or 16420992 counting only the distinct ones).

The product of its (nonzero) digits is 15052800, while the sum is 59.

The spelling of 1278518738540 in words is "one trillion, two hundred seventy-eight billion, five hundred eighteen million, seven hundred thirty-eight thousand, five hundred forty".