138547973 has 2 divisors, whose sum is σ = 138547974. Its totient is φ = 138547972.

The previous prime is 138547957. The next prime is 138548023. The reversal of 138547973 is 379745831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 88322404 + 50225569 = 9398^2 + 7087^2 .

It is a cyclic number.

It is not a de Polignac number, because 138547973 - 2⁴ = 138547957 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138547273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69273986 + 69273987.

It is an arithmetic number, because the mean of its divisors is an integer number (69273987).

Almost surely, 2^138547973 is an apocalyptic number.

It is an amenable number.

138547973 is a deficient number, since it is larger than the sum of its proper divisors (1).

138547973 is an equidigital number, since it uses as much as digits as its factorization.

138547973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 635040, while the sum is 47.

The square root of 138547973 is about 11770.6402969422. The cubic root of 138547973 is about 517.4480151909.

The spelling of 138547973 in words is "one hundred thirty-eight million, five hundred forty-seven thousand, nine hundred seventy-three".