138427723 has 4 divisors (see below), whose sum is σ = 158203120. Its totient is φ = 118652328.

The previous prime is 138427699. The next prime is 138427733. The reversal of 138427723 is 327724831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 327724831 = 7 ⋅46817833.

It is a cyclic number.

It is not a de Polignac number, because 138427723 - 2¹³ = 138419531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138427733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9887688 + ... + 9887701.

It is an arithmetic number, because the mean of its divisors is an integer number (39550780).

Almost surely, 2^138427723 is an apocalyptic number.

138427723 is a deficient number, since it is larger than the sum of its proper divisors (19775397).

138427723 is an equidigital number, since it uses as much as digits as its factorization.

138427723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19775396.

The product of its digits is 56448, while the sum is 37.

The square root of 138427723 is about 11765.5311397319. The cubic root of 138427723 is about 517.2982689022.

The spelling of 138427723 in words is "one hundred thirty-eight million, four hundred twenty-seven thousand, seven hundred twenty-three".