27128661 has 16 divisors (see below), whose sum is σ = 43137024. Its totient is φ = 14827824.

The previous prime is 27128653. The next prime is 27128671. The reversal of 27128661 is 16682172.

It is not a de Polignac number, because 27128661 - 2³ = 27128653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27128641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27601 + ... + 28566.

It is an arithmetic number, because the mean of its divisors is an integer number (2696064).

Almost surely, 2^27128661 is an apocalyptic number.

27128661 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

27128661 is a deficient number, since it is larger than the sum of its proper divisors (16008363).

27128661 is a wasteful number, since it uses less digits than its factorization.

27128661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56200.

The product of its digits is 8064, while the sum is 33.

The square root of 27128661 is about 5208.5181193887. The cubic root of 27128661 is about 300.4757673083.

The spelling of 27128661 in words is "twenty-seven million, one hundred twenty-eight thousand, six hundred sixty-one".