139531537 has 2 divisors, whose sum is σ = 139531538. Its totient is φ = 139531536.

The previous prime is 139531489. The next prime is 139531571. The reversal of 139531537 is 735135931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127148176 + 12383361 = 11276^2 + 3519^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-139531537 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 139531496 and 139531505.

It is not a weakly prime, because it can be changed into another prime (139531237) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69765768 + 69765769.

It is an arithmetic number, because the mean of its divisors is an integer number (69765769).

Almost surely, 2^139531537 is an apocalyptic number.

It is an amenable number.

139531537 is a deficient number, since it is larger than the sum of its proper divisors (1).

139531537 is an equidigital number, since it uses as much as digits as its factorization.

139531537 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42525, while the sum is 37.

The square root of 139531537 is about 11812.3468032394. The cubic root of 139531537 is about 518.6695983776.

The spelling of 139531537 in words is "one hundred thirty-nine million, five hundred thirty-one thousand, five hundred thirty-seven".