138732197 has 4 divisors (see below), whose sum is σ = 139170156. Its totient is φ = 138294240.

The previous prime is 138732173. The next prime is 138732199. The reversal of 138732197 is 791237831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21031396 + 117700801 = 4586^2 + 10849^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138732197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138732199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218504 + ... + 219137.

It is an arithmetic number, because the mean of its divisors is an integer number (34792539).

Almost surely, 2^138732197 is an apocalyptic number.

It is an amenable number.

138732197 is a deficient number, since it is larger than the sum of its proper divisors (437959).

138732197 is an equidigital number, since it uses as much as digits as its factorization.

138732197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437958.

The product of its digits is 63504, while the sum is 41.

The square root of 138732197 is about 11778.4632698837. The cubic root of 138732197 is about 517.6772597892.

The spelling of 138732197 in words is "one hundred thirty-eight million, seven hundred thirty-two thousand, one hundred ninety-seven".