21040601 has 2 divisors, whose sum is σ = 21040602. Its totient is φ = 21040600.

The previous prime is 21040559. The next prime is 21040627. The reversal of 21040601 is 10604012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11424400 + 9616201 = 3380^2 + 3101^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21040601 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21040651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520300 + 10520301.

It is an arithmetic number, because the mean of its divisors is an integer number (10520301).

Almost surely, 2^21040601 is an apocalyptic number.

It is an amenable number.

21040601 is a deficient number, since it is larger than the sum of its proper divisors (1).

21040601 is an equidigital number, since it uses as much as digits as its factorization.

21040601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21040601 is about 4587.0034881173. The cubic root of 21040601 is about 276.0701048899.

Adding to 21040601 its reverse (10604012), we get a palindrome (31644613).

The spelling of 21040601 in words is "twenty-one million, forty thousand, six hundred one".