1378072813 has 6 divisors (see below), whose sum is σ = 1492232874. Its totient is φ = 1272067056.

The previous prime is 1378072783. The next prime is 1378072823. The reversal of 1378072813 is 3182708731.

It can be written as a sum of positive squares in 3 ways, for example, as 29929 + 1378042884 = 173^2 + 37122^2 .

It is not a de Polignac number, because 1378072813 - 2⁵ = 1378072781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378072823) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4076970 + ... + 4077307.

It is an arithmetic number, because the mean of its divisors is an integer number (248705479).

Almost surely, 2^1378072813 is an apocalyptic number.

1378072813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1378072813 is a deficient number, since it is larger than the sum of its proper divisors (114160061).

1378072813 is an equidigital number, since it uses as much as digits as its factorization.

1378072813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8154303 (or 8154290 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 1378072813 is about 37122.4031145614. The cubic root of 1378072813 is about 1112.8177774695.

The spelling of 1378072813 in words is "one billion, three hundred seventy-eight million, seventy-two thousand, eight hundred thirteen".