138403217 has 2 divisors, whose sum is σ = 138403218. Its totient is φ = 138403216.

The previous prime is 138403183. The next prime is 138403231. The reversal of 138403217 is 712304831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131767441 + 6635776 = 11479^2 + 2576^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138403217 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138403217.

It is not a weakly prime, because it can be changed into another prime (138403267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69201608 + 69201609.

It is an arithmetic number, because the mean of its divisors is an integer number (69201609).

Almost surely, 2^138403217 is an apocalyptic number.

It is an amenable number.

138403217 is a deficient number, since it is larger than the sum of its proper divisors (1).

138403217 is an equidigital number, since it uses as much as digits as its factorization.

138403217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 138403217 is about 11764.4896616895. The cubic root of 138403217 is about 517.2677411552.

The spelling of 138403217 in words is "one hundred thirty-eight million, four hundred three thousand, two hundred seventeen".