1278115720 has 64 divisors (see below), whose sum is σ = 3328243200. Its totient is φ = 432656640.

The previous prime is 1278115627. The next prime is 1278115823. The reversal of 1278115720 is 275118721.

It is a super-2 number, since 2×1278115720² = 3267159587422236800, which contains 22 as substring.

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, 6771 + ... + 51010.

It is an arithmetic number, because the mean of its divisors is an integer number (52003800).

Almost surely, 2^1278115720 is an apocalyptic number.

1278115720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1278115720 is an abundant number, since it is smaller than the sum of its proper divisors (2050127480).

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

1278115720 is a wasteful number, since it uses less digits than its factorization.

1278115720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57878 (or 57874 counting only the distinct ones).

The product of its (nonzero) digits is 7840, while the sum is 34.

The square root of 1278115720 is about 35750.7443279157. The cubic root of 1278115720 is about 1085.2340013604.

The spelling of 1278115720 in words is "one billion, two hundred seventy-eight million, one hundred fifteen thousand, seven hundred twenty".