1878691390441 has 4 divisors (see below), whose sum is σ = 1960373624832. Its totient is φ = 1797009156052.

The previous prime is 1878691390417. The next prime is 1878691390447. The reversal of 1878691390441 is 1440931968781.

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 a cyclic number.

It is not a de Polignac number, because 1878691390441 - 2¹¹ = 1878691388393 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 1878691390441.

It is not an unprimeable number, because it can be changed into a prime (1878691390447) 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, 40841117161 + ... + 40841117206.

It is an arithmetic number, because the mean of its divisors is an integer number (490093406208).

Almost surely, 2^{1878691390441} is an apocalyptic number.

It is an amenable number.

1878691390441 is a deficient number, since it is larger than the sum of its proper divisors (81682234391).

1878691390441 is an equidigital number, since it uses as much as digits as its factorization.

1878691390441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81682234390.

The product of its (nonzero) digits is 10450944, while the sum is 61.

The spelling of 1878691390441 in words is "one trillion, eight hundred seventy-eight billion, six hundred ninety-one million, three hundred ninety thousand, four hundred forty-one".