138607481 has 2 divisors, whose sum is σ = 138607482. Its totient is φ = 138607480.

The previous prime is 138607463. The next prime is 138607493. The reversal of 138607481 is 184706831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 132457081 + 6150400 = 11509^2 + 2480^2 .

It is a cyclic number.

It is not a de Polignac number, because 138607481 - 2¹⁴ = 138591097 is a prime.

It is a super-2 number, since 2×138607481² = 38424067578330722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138601481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69303740 + 69303741.

It is an arithmetic number, because the mean of its divisors is an integer number (69303741).

Almost surely, 2^138607481 is an apocalyptic number.

It is an amenable number.

138607481 is a deficient number, since it is larger than the sum of its proper divisors (1).

138607481 is an equidigital number, since it uses as much as digits as its factorization.

138607481 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 138607481 is about 11773.1678404752. The cubic root of 138607481 is about 517.5220879430.

The spelling of 138607481 in words is "one hundred thirty-eight million, six hundred seven thousand, four hundred eighty-one".