138477949 has 2 divisors, whose sum is σ = 138477950. Its totient is φ = 138477948.

The previous prime is 138477919. The next prime is 138477959. The reversal of 138477949 is 949774831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73788100 + 64689849 = 8590^2 + 8043^2 .

It is a cyclic number.

It is not a de Polignac number, because 138477949 - 2⁷ = 138477821 is a prime.

It is a super-2 number, since 2×138477949² = 38352284718493202, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138477896 and 138477905.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138477919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69238974 + 69238975.

It is an arithmetic number, because the mean of its divisors is an integer number (69238975).

Almost surely, 2^138477949 is an apocalyptic number.

It is an amenable number.

138477949 is a deficient number, since it is larger than the sum of its proper divisors (1).

138477949 is an equidigital number, since it uses as much as digits as its factorization.

138477949 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1524096, while the sum is 52.

The square root of 138477949 is about 11767.6654014295. The cubic root of 138477949 is about 517.3608254493.

The spelling of 138477949 in words is "one hundred thirty-eight million, four hundred seventy-seven thousand, nine hundred forty-nine".