138805057 has 2 divisors, whose sum is σ = 138805058. Its totient is φ = 138805056.

The previous prime is 138805027. The next prime is 138805061. The reversal of 138805057 is 750508831.

138805057 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 136445761 + 2359296 = 11681^2 + 1536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138805057 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138805027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69402528 + 69402529.

It is an arithmetic number, because the mean of its divisors is an integer number (69402529).

Almost surely, 2^138805057 is an apocalyptic number.

It is an amenable number.

138805057 is a deficient number, since it is larger than the sum of its proper divisors (1).

138805057 is an equidigital number, since it uses as much as digits as its factorization.

138805057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 138805057 is about 11781.5557970923. Note that the first 3 decimals coincide. The cubic root of 138805057 is about 517.7678692870.

The spelling of 138805057 in words is "one hundred thirty-eight million, eight hundred five thousand, fifty-seven".