138645651 has 4 divisors (see below), whose sum is σ = 184860872. Its totient is φ = 92430432.

The previous prime is 138645643. The next prime is 138645667. The reversal of 138645651 is 156546831.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 138645651 - 2³ = 138645643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138645691) 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, 23107606 + ... + 23107611.

It is an arithmetic number, because the mean of its divisors is an integer number (46215218).

Almost surely, 2^138645651 is an apocalyptic number.

138645651 is a deficient number, since it is larger than the sum of its proper divisors (46215221).

138645651 is an equidigital number, since it uses as much as digits as its factorization.

138645651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46215220.

The product of its digits is 86400, while the sum is 39.

The square root of 138645651 is about 11774.7887879146. The cubic root of 138645651 is about 517.5695889989.

The spelling of 138645651 in words is "one hundred thirty-eight million, six hundred forty-five thousand, six hundred fifty-one".