1278765140 has 24 divisors (see below), whose sum is σ = 2757986952. Its totient is φ = 497681280.

The previous prime is 1278765139. The next prime is 1278765197. The reversal of 1278765140 is 415678721.

It can be written as a sum of positive squares in 4 ways, for example, as 200562244 + 1078202896 = 14162^2 + 32836^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 863291 + ... + 864770.

It is an arithmetic number, because the mean of its divisors is an integer number (114916123).

Almost surely, 2^1278765140 is an apocalyptic number.

1278765140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1278765140 is an abundant number, since it is smaller than the sum of its proper divisors (1479221812).

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

1278765140 is a wasteful number, since it uses less digits than its factorization.

1278765140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1728107 (or 1728105 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 41.

The square root of 1278765140 is about 35759.8257825734. The cubic root of 1278765140 is about 1085.4177753648.

The spelling of 1278765140 in words is "one billion, two hundred seventy-eight million, seven hundred sixty-five thousand, one hundred forty".