1378640037865 has 16 divisors (see below), whose sum is σ = 1671708641616. Its totient is φ = 1091364192000.

The previous prime is 1378640037839. The next prime is 1378640037913. The reversal of 1378640037865 is 5687300468731.

It can be written as a sum of positive squares in 8 ways, for example, as 239946164649 + 1138693873216 = 489843^2 + 1067096^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1378640037865 is a prime.

It is a Duffinian number.

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, 95179 + ... + 1663231.

It is an arithmetic number, because the mean of its divisors is an integer number (104481790101).

Almost surely, 2^{1378640037865} is an apocalyptic number.

It is an amenable number.

1378640037865 is a deficient number, since it is larger than the sum of its proper divisors (293068603751).

1378640037865 is a wasteful number, since it uses less digits than its factorization.

1378640037865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1569900.

The product of its (nonzero) digits is 20321280, while the sum is 58.

The spelling of 1378640037865 in words is "one trillion, three hundred seventy-eight billion, six hundred forty million, thirty-seven thousand, eight hundred sixty-five".