27573606661 has 2 divisors, whose sum is σ = 27573606662. Its totient is φ = 27573606660.

The previous prime is 27573606629. The next prime is 27573606677. The reversal of 27573606661 is 16660637572.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23675976900 + 3897629761 = 153870^2 + 62431^2 .

It is a cyclic number.

It is not a de Polignac number, because 27573606661 - 2⁵ = 27573606629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27573606601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13786803330 + 13786803331.

It is an arithmetic number, because the mean of its divisors is an integer number (13786803331).

Almost surely, 2^27573606661 is an apocalyptic number.

It is an amenable number.

27573606661 is a deficient number, since it is larger than the sum of its proper divisors (1).

27573606661 is an equidigital number, since it uses as much as digits as its factorization.

27573606661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1905120, while the sum is 49.

The spelling of 27573606661 in words is "twenty-seven billion, five hundred seventy-three million, six hundred six thousand, six hundred sixty-one".