1381199279 has 2 divisors, whose sum is σ = 1381199280. Its totient is φ = 1381199278.

The previous prime is 1381199207. The next prime is 1381199297. The reversal of 1381199279 is 9729911831.

Together with next prime (1381199297) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1381199279 - 2²⁰ = 1380150703 is a prime.

It is a super-2 number, since 2×1381199279² = 3815422896620239682, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1381199299) by changing a digit.

It is an upside-down number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 690599639 + 690599640.

It is an arithmetic number, because the mean of its divisors is an integer number (690599640).

Almost surely, 2^1381199279 is an apocalyptic number.

1381199279 is a deficient number, since it is larger than the sum of its proper divisors (1).

1381199279 is an equidigital number, since it uses as much as digits as its factorization.

1381199279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944, while the sum is 50.

The square root of 1381199279 is about 37164.4894892961. The cubic root of 1381199279 is about 1113.6587004163.

The spelling of 1381199279 in words is "one billion, three hundred eighty-one million, one hundred ninety-nine thousand, two hundred seventy-nine".