138513761 has 2 divisors, whose sum is σ = 138513762. Its totient is φ = 138513760.

The previous prime is 138513733. The next prime is 138513779. The reversal of 138513761 is 167315831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80281600 + 58232161 = 8960^2 + 7631^2 .

It is a cyclic number.

It is not a de Polignac number, because 138513761 - 2¹⁴ = 138497377 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138513731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69256880 + 69256881.

It is an arithmetic number, because the mean of its divisors is an integer number (69256881).

Almost surely, 2^138513761 is an apocalyptic number.

It is an amenable number.

138513761 is a deficient number, since it is larger than the sum of its proper divisors (1).

138513761 is an equidigital number, since it uses as much as digits as its factorization.

138513761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 35.

The square root of 138513761 is about 11769.1869302854. The cubic root of 138513761 is about 517.4054201040.

The spelling of 138513761 in words is "one hundred thirty-eight million, five hundred thirteen thousand, seven hundred sixty-one".