21340441 has 2 divisors, whose sum is σ = 21340442. Its totient is φ = 21340440.

The previous prime is 21340421. The next prime is 21340469. The reversal of 21340441 is 14404312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16232841 + 5107600 = 4029^2 + 2260^2 .

It is a cyclic number.

It is not a de Polignac number, because 21340441 - 2⁵ = 21340409 is a prime.

It is equal to p_1350127 and since 21340441 and 1350127 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (21340411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10670220 + 10670221.

It is an arithmetic number, because the mean of its divisors is an integer number (10670221).

Almost surely, 2^21340441 is an apocalyptic number.

It is an amenable number.

21340441 is a deficient number, since it is larger than the sum of its proper divisors (1).

21340441 is an equidigital number, since it uses as much as digits as its factorization.

21340441 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 21340441 is about 4619.5715169267. The cubic root of 21340441 is about 277.3753074503.

Adding to 21340441 its reverse (14404312), we get a palindrome (35744753).

The spelling of 21340441 in words is "twenty-one million, three hundred forty thousand, four hundred forty-one".