138748561 has 8 divisors (see below), whose sum is σ = 158716544. Its totient is φ = 118817280.

The previous prime is 138748523. The next prime is 138748567. The reversal of 138748561 is 165847831.

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

It is a cyclic number.

It is not a de Polignac number, because 138748561 - 2²³ = 130359953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138748567) 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, 525 + ... + 16666.

It is an arithmetic number, because the mean of its divisors is an integer number (19839568).

Almost surely, 2^138748561 is an apocalyptic number.

It is an amenable number.

138748561 is a deficient number, since it is larger than the sum of its proper divisors (19967983).

138748561 is a wasteful number, since it uses less digits than its factorization.

138748561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18351.

The product of its digits is 161280, while the sum is 43.

The square root of 138748561 is about 11779.1579070832. The cubic root of 138748561 is about 517.6976130016.

The spelling of 138748561 in words is "one hundred thirty-eight million, seven hundred forty-eight thousand, five hundred sixty-one".