21671341 has 2 divisors, whose sum is σ = 21671342. Its totient is φ = 21671340.

The previous prime is 21671333. The next prime is 21671347. The reversal of 21671341 is 14317612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21622500 + 48841 = 4650^2 + 221^2 .

It is a cyclic number.

It is not a de Polignac number, because 21671341 - 2³ = 21671333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21671347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10835670 + 10835671.

It is an arithmetic number, because the mean of its divisors is an integer number (10835671).

Almost surely, 2^21671341 is an apocalyptic number.

It is an amenable number.

21671341 is a deficient number, since it is larger than the sum of its proper divisors (1).

21671341 is an equidigital number, since it uses as much as digits as its factorization.

21671341 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 25.

The square root of 21671341 is about 4655.2487581224. The cubic root of 21671341 is about 278.8016001053.

Adding to 21671341 its reverse (14317612), we get a palindrome (35988953).

The spelling of 21671341 in words is "twenty-one million, six hundred seventy-one thousand, three hundred forty-one".