138890441 has 2 divisors, whose sum is σ = 138890442. Its totient is φ = 138890440.

The previous prime is 138890429. The next prime is 138890443. The reversal of 138890441 is 144098831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 136422400 + 2468041 = 11680^2 + 1571^2 .

It is a cyclic number.

It is not a de Polignac number, because 138890441 - 2⁶ = 138890377 is a prime.

It is a Sophie Germain prime.

Together with 138890443, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 138890395 and 138890404.

It is not a weakly prime, because it can be changed into another prime (138890443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69445220 + 69445221.

It is an arithmetic number, because the mean of its divisors is an integer number (69445221).

Almost surely, 2^138890441 is an apocalyptic number.

It is an amenable number.

138890441 is a deficient number, since it is larger than the sum of its proper divisors (1).

138890441 is an equidigital number, since it uses as much as digits as its factorization.

138890441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 138890441 is about 11785.1788700893. The cubic root of 138890441 is about 517.8740134265.

The spelling of 138890441 in words is "one hundred thirty-eight million, eight hundred ninety thousand, four hundred forty-one".