138002281 has 2 divisors, whose sum is σ = 138002282. Its totient is φ = 138002280.

The previous prime is 138002257. The next prime is 138002303. The reversal of 138002281 is 182200831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123409881 + 14592400 = 11109^2 + 3820^2 .

It is an emirp because it is prime and its reverse (182200831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138002281 is a prime.

It is a super-2 number, since 2×138002281² = 38089259122405922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138002201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69001140 + 69001141.

It is an arithmetic number, because the mean of its divisors is an integer number (69001141).

Almost surely, 2^138002281 is an apocalyptic number.

It is an amenable number.

138002281 is a deficient number, since it is larger than the sum of its proper divisors (1).

138002281 is an equidigital number, since it uses as much as digits as its factorization.

138002281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 138002281 is about 11747.4372098769. The cubic root of 138002281 is about 516.7677724207.

The spelling of 138002281 in words is "one hundred thirty-eight million, two thousand, two hundred eighty-one".