138891661511 has 8 divisors (see below), whose sum is σ = 141517919664. Its totient is φ = 136265613120.

The previous prime is 138891661507. The next prime is 138891661523. The reversal of 138891661511 is 115166198831.

It is a happy number.

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 138891661511 - 2² = 138891661507 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138891661511.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138891661561) 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, 2149700 + ... + 2213366.

It is an arithmetic number, because the mean of its divisors is an integer number (17689739958).

Almost surely, 2^138891661511 is an apocalyptic number.

138891661511 is a deficient number, since it is larger than the sum of its proper divisors (2626258153).

138891661511 is an equidigital number, since it uses as much as digits as its factorization.

138891661511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104881.

The product of its digits is 311040, while the sum is 50.

The spelling of 138891661511 in words is "one hundred thirty-eight billion, eight hundred ninety-one million, six hundred sixty-one thousand, five hundred eleven".