1389326993 has 2 divisors, whose sum is σ = 1389326994. Its totient is φ = 1389326992.

The previous prime is 1389326959. The next prime is 1389326999. The reversal of 1389326993 is 3996239831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1279349824 + 109977169 = 35768^2 + 10487^2 .

It is a cyclic number.

It is not a de Polignac number, because 1389326993 - 2²⁰ = 1388278417 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1389326999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694663496 + 694663497.

It is an arithmetic number, because the mean of its divisors is an integer number (694663497).

Almost surely, 2^1389326993 is an apocalyptic number.

It is an amenable number.

1389326993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1389326993 is an equidigital number, since it uses as much as digits as its factorization.

1389326993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1889568, while the sum is 53.

The square root of 1389326993 is about 37273.6769449970. The cubic root of 1389326993 is about 1115.8388836686.

The spelling of 1389326993 in words is "one billion, three hundred eighty-nine million, three hundred twenty-six thousand, nine hundred ninety-three".