138719561 has 8 divisors (see below), whose sum is σ = 142473600. Its totient is φ = 135012400.

The previous prime is 138719543. The next prime is 138719563. The reversal of 138719561 is 165917831.

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 138719561 - 2¹⁰ = 138718537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138719563) 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, 5681 + ... + 17598.

It is an arithmetic number, because the mean of its divisors is an integer number (17809200).

Almost surely, 2^138719561 is an apocalyptic number.

It is an amenable number.

138719561 is a deficient number, since it is larger than the sum of its proper divisors (3754039).

138719561 is a wasteful number, since it uses less digits than its factorization.

138719561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23439.

The product of its digits is 45360, while the sum is 41.

The square root of 138719561 is about 11777.9268549265. The cubic root of 138719561 is about 517.6615422927.

It can be divided in two parts, 13871 and 9561, that added together give a palindrome (23432).

The spelling of 138719561 in words is "one hundred thirty-eight million, seven hundred nineteen thousand, five hundred sixty-one".