138878642533 has 4 divisors (see below), whose sum is σ = 138897542368. Its totient is φ = 138859742700.

The previous prime is 138878642509. The next prime is 138878642557. The reversal of 138878642533 is 335246878831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (138878642509) and next prime (138878642557).

It is a cyclic number.

It is not a de Polignac number, because 138878642533 - 2²⁵ = 138845088101 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138878642633) 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, 9438891 + ... + 9453592.

It is an arithmetic number, because the mean of its divisors is an integer number (34724385592).

Almost surely, 2^138878642533 is an apocalyptic number.

It is an amenable number.

138878642533 is a deficient number, since it is larger than the sum of its proper divisors (18899835).

138878642533 is an equidigital number, since it uses as much as digits as its factorization.

138878642533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18899834.

The product of its digits is 23224320, while the sum is 58.

The spelling of 138878642533 in words is "one hundred thirty-eight billion, eight hundred seventy-eight million, six hundred forty-two thousand, five hundred thirty-three".