139240237 has 2 divisors, whose sum is σ = 139240238. Its totient is φ = 139240236.

The previous prime is 139240201. The next prime is 139240267. The reversal of 139240237 is 732042931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 135163876 + 4076361 = 11626^2 + 2019^2 .

It is an emirp because it is prime and its reverse (732042931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 139240237 - 2¹⁹ = 138715949 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 139240199 and 139240208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139240267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69620118 + 69620119.

It is an arithmetic number, because the mean of its divisors is an integer number (69620119).

Almost surely, 2^139240237 is an apocalyptic number.

It is an amenable number.

139240237 is a deficient number, since it is larger than the sum of its proper divisors (1).

139240237 is an equidigital number, since it uses as much as digits as its factorization.

139240237 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 139240237 is about 11800.0100423686. The cubic root of 139240237 is about 518.3084047201.

The spelling of 139240237 in words is "one hundred thirty-nine million, two hundred forty thousand, two hundred thirty-seven".