1881608139685 has 8 divisors (see below), whose sum is σ = 2259532281240. Its totient is φ = 1504218169344.

The previous prime is 1881608139643. The next prime is 1881608139709. The reversal of 1881608139685 is 5869318061881.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 223493508001 + 1658114631684 = 472751^2 + 1287678^2 .

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 1881608139685 - 2¹⁹ = 1881607615397 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133535052 + ... + 133549141.

It is an arithmetic number, because the mean of its divisors is an integer number (282441535155).

Almost surely, 2^{1881608139685} is an apocalyptic number.

It is an amenable number.

1881608139685 is a deficient number, since it is larger than the sum of its proper divisors (377924141555).

1881608139685 is a wasteful number, since it uses less digits than its factorization.

1881608139685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267085607.

The product of its (nonzero) digits is 19906560, while the sum is 64.

The spelling of 1881608139685 in words is "one trillion, eight hundred eighty-one billion, six hundred eight million, one hundred thirty-nine thousand, six hundred eighty-five".