21011741 has 2 divisors, whose sum is σ = 21011742. Its totient is φ = 21011740.

The previous prime is 21011713. The next prime is 21011759. The reversal of 21011741 is 14711012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17935225 + 3076516 = 4235^2 + 1754^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011741 is a prime.

It is a Chen prime.

It is a plaindrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011761) 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, 10505870 + 10505871.

It is an arithmetic number, because the mean of its divisors is an integer number (10505871).

Almost surely, 2^21011741 is an apocalyptic number.

It is an amenable number.

21011741 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011741 is an equidigital number, since it uses as much as digits as its factorization.

21011741 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56, while the sum is 17.

The square root of 21011741 is about 4583.8565640735. The cubic root of 21011741 is about 275.9438247711.

Adding to 21011741 its reverse (14711012), we get a palindrome (35722753).

The spelling of 21011741 in words is "twenty-one million, eleven thousand, seven hundred forty-one".