139234561 has 2 divisors, whose sum is σ = 139234562. Its totient is φ = 139234560.

The previous prime is 139234553. The next prime is 139234591. The reversal of 139234561 is 165432931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 94945536 + 44289025 = 9744^2 + 6655^2 .

It is a cyclic number.

It is not a de Polignac number, because 139234561 - 2³ = 139234553 is a prime.

It is not a weakly prime, because it can be changed into another prime (139234541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69617280 + 69617281.

It is an arithmetic number, because the mean of its divisors is an integer number (69617281).

Almost surely, 2^139234561 is an apocalyptic number.

It is an amenable number.

139234561 is a deficient number, since it is larger than the sum of its proper divisors (1).

139234561 is an equidigital number, since it uses as much as digits as its factorization.

139234561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19440, while the sum is 34.

The square root of 139234561 is about 11799.7695316476. The cubic root of 139234561 is about 518.3013618362.

It can be divided in two parts, 1392 and 34561, that added together give a palindrome (35953).

The spelling of 139234561 in words is "one hundred thirty-nine million, two hundred thirty-four thousand, five hundred sixty-one".