138402923 has 2 divisors, whose sum is σ = 138402924. Its totient is φ = 138402922.

The previous prime is 138402893. The next prime is 138402931. The reversal of 138402923 is 329204831.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (329204831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138402923 - 2²² = 134208619 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138402923.

It is not a weakly prime, because it can be changed into another prime (138405923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69201461 + 69201462.

It is an arithmetic number, because the mean of its divisors is an integer number (69201462).

Almost surely, 2^138402923 is an apocalyptic number.

138402923 is a deficient number, since it is larger than the sum of its proper divisors (1).

138402923 is an equidigital number, since it uses as much as digits as its factorization.

138402923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 32.

The square root of 138402923 is about 11764.4771664533. The cubic root of 138402923 is about 517.2673748900.

The spelling of 138402923 in words is "one hundred thirty-eight million, four hundred two thousand, nine hundred twenty-three".