1378416691 has 2 divisors, whose sum is σ = 1378416692. Its totient is φ = 1378416690.

The previous prime is 1378416667. The next prime is 1378416707. The reversal of 1378416691 is 1966148731.

It is a strong prime.

It is an emirp because it is prime and its reverse (1966148731) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1378416691 - 2¹⁹ = 1377892403 is a prime.

It is not a weakly prime, because it can be changed into another prime (1378516691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 689208345 + 689208346.

It is an arithmetic number, because the mean of its divisors is an integer number (689208346).

Almost surely, 2^1378416691 is an apocalyptic number.

1378416691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1378416691 is an equidigital number, since it uses as much as digits as its factorization.

1378416691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 46.

The square root of 1378416691 is about 37127.0345031757. The cubic root of 1378416691 is about 1112.9103322611.

The spelling of 1378416691 in words is "one billion, three hundred seventy-eight million, four hundred sixteen thousand, six hundred ninety-one".