21711097 has 2 divisors, whose sum is σ = 21711098. Its totient is φ = 21711096.

The previous prime is 21711083. The next prime is 21711101. The reversal of 21711097 is 79011712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21678336 + 32761 = 4656^2 + 181^2 .

It is a cyclic number.

It is not a de Polignac number, because 21711097 - 2¹⁵ = 21678329 is a prime.

It is not a weakly prime, because it can be changed into another prime (21711037) 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, 10855548 + 10855549.

It is an arithmetic number, because the mean of its divisors is an integer number (10855549).

Almost surely, 2^21711097 is an apocalyptic number.

It is an amenable number.

21711097 is a deficient number, since it is larger than the sum of its proper divisors (1).

21711097 is an equidigital number, since it uses as much as digits as its factorization.

21711097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 882, while the sum is 28.

The square root of 21711097 is about 4659.5168204439. The cubic root of 21711097 is about 278.9719828154.

The spelling of 21711097 in words is "twenty-one million, seven hundred eleven thousand, ninety-seven".