27781957357 has 16 divisors (see below), whose sum is σ = 34644334464. Its totient is φ = 21643848000.

The previous prime is 27781957351. The next prime is 27781957373. The reversal of 27781957357 is 75375918772.

It is a cyclic number.

It is not a de Polignac number, because 27781957357 - 2³ = 27781957349 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 27781957295 and 27781957304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27781957351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 370807 + ... + 439387.

It is an arithmetic number, because the mean of its divisors is an integer number (2165270904).

Almost surely, 2^27781957357 is an apocalyptic number.

It is an amenable number.

27781957357 is a deficient number, since it is larger than the sum of its proper divisors (6862377107).

27781957357 is a wasteful number, since it uses less digits than its factorization.

27781957357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73860.

The product of its digits is 25930800, while the sum is 61.

The spelling of 27781957357 in words is "twenty-seven billion, seven hundred eighty-one million, nine hundred fifty-seven thousand, three hundred fifty-seven".