2578363591681 has 8 divisors (see below), whose sum is σ = 2635685700480. Its totient is φ = 2521144120848.

The previous prime is 2578363591669. The next prime is 2578363591709. The reversal of 2578363591681 is 1861953638752.

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 2578363591681 - 2²⁹ = 2577826720769 is a prime.

It is a super-2 number, since 2×2578363591681² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2578363591781) 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, 25608691 + ... + 25709176.

It is an arithmetic number, because the mean of its divisors is an integer number (329460712560).

Almost surely, 2^{2578363591681} is an apocalyptic number.

It is an amenable number.

2578363591681 is a deficient number, since it is larger than the sum of its proper divisors (57322108799).

2578363591681 is a wasteful number, since it uses less digits than its factorization.

2578363591681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51318983.

The product of its digits is 65318400, while the sum is 64.

The spelling of 2578363591681 in words is "two trillion, five hundred seventy-eight billion, three hundred sixty-three million, five hundred ninety-one thousand, six hundred eighty-one".