138749929 has 4 divisors (see below), whose sum is σ = 141024580. Its totient is φ = 136475280.

The previous prime is 138749921. The next prime is 138749953. The reversal of 138749929 is 929947831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 929947831 = 1447 ⋅642673.

It can be written as a sum of positive squares in 2 ways, for example, as 49730704 + 89019225 = 7052^2 + 9435^2 .

It is a cyclic number.

It is not a de Polignac number, because 138749929 - 2³ = 138749921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138749921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1137234 + ... + 1137355.

It is an arithmetic number, because the mean of its divisors is an integer number (35256145).

Almost surely, 2^138749929 is an apocalyptic number.

It is an amenable number.

138749929 is a deficient number, since it is larger than the sum of its proper divisors (2274651).

138749929 is an equidigital number, since it uses as much as digits as its factorization.

138749929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2274650.

The product of its digits is 979776, while the sum is 52.

The square root of 138749929 is about 11779.2159756072. The cubic root of 138749929 is about 517.6993144199.

The spelling of 138749929 in words is "one hundred thirty-eight million, seven hundred forty-nine thousand, nine hundred twenty-nine".