138235649 has 4 divisors (see below), whose sum is σ = 138517680. Its totient is φ = 137953620.

The previous prime is 138235633. The next prime is 138235661. The reversal of 138235649 is 946532831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 138235649 - 2⁴ = 138235633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138235609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140279 + ... + 141260.

It is an arithmetic number, because the mean of its divisors is an integer number (34629420).

Almost surely, 2^138235649 is an apocalyptic number.

It is an amenable number.

138235649 is a deficient number, since it is larger than the sum of its proper divisors (282031).

138235649 is an equidigital number, since it uses as much as digits as its factorization.

138235649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282030.

The product of its digits is 155520, while the sum is 41.

The square root of 138235649 is about 11757.3657338708. The cubic root of 138235649 is about 517.0589008139.

The spelling of 138235649 in words is "one hundred thirty-eight million, two hundred thirty-five thousand, six hundred forty-nine".