27761689 has 2 divisors, whose sum is σ = 27761690. Its totient is φ = 27761688.

The previous prime is 27761687. The next prime is 27761707. The reversal of 27761689 is 98616772.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21233664 + 6528025 = 4608^2 + 2555^2 .

It is a cyclic number.

It is not a de Polignac number, because 27761689 - 2¹ = 27761687 is a prime.

It is a super-2 number, since 2×27761689² = 1541422752265442, which contains 22 as substring.

Together with 27761687, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (27761687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13880844 + 13880845.

It is an arithmetic number, because the mean of its divisors is an integer number (13880845).

Almost surely, 2^27761689 is an apocalyptic number.

It is an amenable number.

27761689 is a deficient number, since it is larger than the sum of its proper divisors (1).

27761689 is an equidigital number, since it uses as much as digits as its factorization.

27761689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 254016, while the sum is 46.

The square root of 27761689 is about 5268.9362303979. The cubic root of 27761689 is about 302.7949503476.

It can be divided in two parts, 2776 and 1689, that added together give a triangular number (4465 = T₉₄).

The spelling of 27761689 in words is "twenty-seven million, seven hundred sixty-one thousand, six hundred eighty-nine".