1378513217 has 2 divisors, whose sum is σ = 1378513218. Its totient is φ = 1378513216.

The previous prime is 1378513163. The next prime is 1378513247. The reversal of 1378513217 is 7123158731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 991053361 + 387459856 = 31481^2 + 19684^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1378513217 is a prime.

It is a super-4 number, since 4×1378513217⁴ (a number of 38 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (1378513247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689256608 + 689256609.

It is an arithmetic number, because the mean of its divisors is an integer number (689256609).

Almost surely, 2^1378513217 is an apocalyptic number.

It is an amenable number.

1378513217 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378513217 is an equidigital number, since it uses as much as digits as its factorization.

1378513217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 35280, while the sum is 38.

The square root of 1378513217 is about 37128.3344226482. The cubic root of 1378513217 is about 1112.9363094749.

The spelling of 1378513217 in words is "one billion, three hundred seventy-eight million, five hundred thirteen thousand, two hundred seventeen".