27155221 has 2 divisors, whose sum is σ = 27155222. Its totient is φ = 27155220.

The previous prime is 27155201. The next prime is 27155251. The reversal of 27155221 is 12255172.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13912900 + 13242321 = 3730^2 + 3639^2 .

It is a cyclic number.

It is not a de Polignac number, because 27155221 - 2¹¹ = 27153173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27155201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13577610 + 13577611.

It is an arithmetic number, because the mean of its divisors is an integer number (13577611).

Almost surely, 2^27155221 is an apocalyptic number.

It is an amenable number.

27155221 is a deficient number, since it is larger than the sum of its proper divisors (1).

27155221 is an equidigital number, since it uses as much as digits as its factorization.

27155221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1400, while the sum is 25.

The square root of 27155221 is about 5211.0671651784. The cubic root of 27155221 is about 300.5737944261.

The spelling of 27155221 in words is "twenty-seven million, one hundred fifty-five thousand, two hundred twenty-one".