21080611 has 2 divisors, whose sum is σ = 21080612. Its totient is φ = 21080610.

The previous prime is 21080599. The next prime is 21080617. The reversal of 21080611 is 11608012.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21080611 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21080617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10540305 + 10540306.

It is an arithmetic number, because the mean of its divisors is an integer number (10540306).

Almost surely, 2^21080611 is an apocalyptic number.

21080611 is a deficient number, since it is larger than the sum of its proper divisors (1).

21080611 is an equidigital number, since it uses as much as digits as its factorization.

21080611 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 21080611 is about 4591.3626517625. The cubic root of 21080611 is about 276.2449821983.

Adding to 21080611 its reverse (11608012), we get a palindrome (32688623).

The spelling of 21080611 in words is "twenty-one million, eighty thousand, six hundred eleven".