138649451 has 8 divisors (see below), whose sum is σ = 146305440. Its totient is φ = 131129152.

The previous prime is 138649429. The next prime is 138649457. The reversal of 138649451 is 154946831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138649451 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 138649399 and 138649408.

It is not an unprimeable number, because it can be changed into a prime (138649457) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31820 + ... + 35913.

It is an arithmetic number, because the mean of its divisors is an integer number (18288180).

Almost surely, 2^138649451 is an apocalyptic number.

138649451 is a deficient number, since it is larger than the sum of its proper divisors (7655989).

138649451 is an equidigital number, since it uses as much as digits as its factorization.

138649451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67845.

The product of its digits is 103680, while the sum is 41.

The square root of 138649451 is about 11774.9501485144. The cubic root of 138649451 is about 517.5743174714.

The spelling of 138649451 in words is "one hundred thirty-eight million, six hundred forty-nine thousand, four hundred fifty-one".