139423261 has 2 divisors, whose sum is σ = 139423262. Its totient is φ = 139423260.

The previous prime is 139423237. The next prime is 139423301. The reversal of 139423261 is 162324931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83083225 + 56340036 = 9115^2 + 7506^2 .

It is a cyclic number.

It is not a de Polignac number, because 139423261 - 2²¹ = 137326109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (139423201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69711630 + 69711631.

It is an arithmetic number, because the mean of its divisors is an integer number (69711631).

Almost surely, 2^139423261 is an apocalyptic number.

It is an amenable number.

139423261 is a deficient number, since it is larger than the sum of its proper divisors (1).

139423261 is an equidigital number, since it uses as much as digits as its factorization.

139423261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 31.

The square root of 139423261 is about 11807.7627432126. The cubic root of 139423261 is about 518.5354017092.

The spelling of 139423261 in words is "one hundred thirty-nine million, four hundred twenty-three thousand, two hundred sixty-one".