138215924461 has 4 divisors (see below), whose sum is σ = 138217268124. Its totient is φ = 138214580800.

The previous prime is 138215924419. The next prime is 138215924467. The reversal of 138215924461 is 164429512831.

138215924461 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 164429512831 = 47 ⋅3498500273.

It can be written as a sum of positive squares in 2 ways, for example, as 104195966436 + 34019958025 = 322794^2 + 184445^2 .

It is a cyclic number.

It is not a de Polignac number, because 138215924461 - 2¹⁹ = 138215400173 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 (138215924467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503470 + ... + 727951.

It is an arithmetic number, because the mean of its divisors is an integer number (34554317031).

Almost surely, 2^138215924461 is an apocalyptic number.

It is an amenable number.

138215924461 is a deficient number, since it is larger than the sum of its proper divisors (1343663).

138215924461 is a wasteful number, since it uses less digits than its factorization.

138215924461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1343662.

The product of its digits is 414720, while the sum is 46.

The spelling of 138215924461 in words is "one hundred thirty-eight billion, two hundred fifteen million, nine hundred twenty-four thousand, four hundred sixty-one".