27971929 has 2 divisors, whose sum is σ = 27971930. Its totient is φ = 27971928.

The previous prime is 27971927. The next prime is 27971947. The reversal of 27971929 is 92917972.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25522704 + 2449225 = 5052^2 + 1565^2 .

It is a cyclic number.

It is not a de Polignac number, because 27971929 - 2¹ = 27971927 is a prime.

Together with 27971927, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (27971927) 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, 13985964 + 13985965.

It is an arithmetic number, because the mean of its divisors is an integer number (13985965).

Almost surely, 2^27971929 is an apocalyptic number.

It is an amenable number.

27971929 is a deficient number, since it is larger than the sum of its proper divisors (1).

27971929 is an equidigital number, since it uses as much as digits as its factorization.

27971929 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 142884, while the sum is 46.

The square root of 27971929 is about 5288.8494968188. The cubic root of 27971929 is about 303.5573869610.

It can be divided in two parts, 27971 and 929, that added together give a square (28900 = 170²).

The spelling of 27971929 in words is "twenty-seven million, nine hundred seventy-one thousand, nine hundred twenty-nine".