1393427809 has 2 divisors, whose sum is σ = 1393427810. Its totient is φ = 1393427808.

The previous prime is 1393427779. The next prime is 1393427813. The reversal of 1393427809 is 9087243931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 753337809 + 640090000 = 27447^2 + 25300^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1393427809 is a prime.

It is not a weakly prime, because it can be changed into another prime (1393527809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 696713904 + 696713905.

It is an arithmetic number, because the mean of its divisors is an integer number (696713905).

Almost surely, 2^1393427809 is an apocalyptic number.

It is an amenable number.

1393427809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1393427809 is an equidigital number, since it uses as much as digits as its factorization.

1393427809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 326592, while the sum is 46.

The square root of 1393427809 is about 37328.6459572270. The cubic root of 1393427809 is about 1116.9356629549.

The spelling of 1393427809 in words is "one billion, three hundred ninety-three million, four hundred twenty-seven thousand, eight hundred nine".