27681669 has 10 divisors (see below), whose sum is σ = 41351750. Its totient is φ = 18454392.

The previous prime is 27681571. The next prime is 27681671. The reversal of 27681669 is 96618672.

It can be written as a sum of positive squares in only one way, i.e., 27436644 + 245025 = 5238^2 + 495^2 .

It is not a de Polignac number, because 27681669 - 2⁷ = 27681541 is a prime.

It is a super-2 number, since 2×27681669² = 1532549597251122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27681469) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 170794 + ... + 170955.

It is an arithmetic number, because the mean of its divisors is an integer number (4135175).

Almost surely, 2^27681669 is an apocalyptic number.

It is an amenable number.

27681669 is a deficient number, since it is larger than the sum of its proper divisors (13670081).

27681669 is an equidigital number, since it uses as much as digits as its factorization.

27681669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341761 (or 341752 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 27681669 is about 5261.3371874458. The cubic root of 27681669 is about 302.5037460547.

The spelling of 27681669 in words is "twenty-seven million, six hundred eighty-one thousand, six hundred sixty-nine".