27827821577 has 6 divisors (see below), whose sum is σ = 29465480538. Its totient is φ = 26190243552.

The previous prime is 27827821573. The next prime is 27827821613. The reversal of 27827821577 is 77512872872.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 26190890896 + 1636930681 = 161836^2 + 40459^2 .

It is not a de Polignac number, because 27827821577 - 2² = 27827821573 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27827821573) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 667574 + ... + 708032.

It is an arithmetic number, because the mean of its divisors is an integer number (4910913423).

Almost surely, 2^27827821577 is an apocalyptic number.

It is an amenable number.

27827821577 is a deficient number, since it is larger than the sum of its proper divisors (1637658961).

27827821577 is an frugal number, since it uses more digits than its factorization.

27827821577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80935 (or 40476 counting only the distinct ones).

The product of its digits is 6146560, while the sum is 56.

The spelling of 27827821577 in words is "twenty-seven billion, eight hundred twenty-seven million, eight hundred twenty-one thousand, five hundred seventy-seven".