21340367 has 2 divisors, whose sum is σ = 21340368. Its totient is φ = 21340366.

The previous prime is 21340351. The next prime is 21340373. The reversal of 21340367 is 76304312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21340367 - 2⁴ = 21340351 is a prime.

It is a super-2 number, since 2×21340367² = 910822527389378, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21340327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10670183 + 10670184.

It is an arithmetic number, because the mean of its divisors is an integer number (10670184).

Almost surely, 2^21340367 is an apocalyptic number.

21340367 is a deficient number, since it is larger than the sum of its proper divisors (1).

21340367 is an equidigital number, since it uses as much as digits as its factorization.

21340367 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 21340367 is about 4619.5635075189. The cubic root of 21340367 is about 277.3749868416.

Adding to 21340367 its reverse (76304312), we get a palindrome (97644679).

The spelling of 21340367 in words is "twenty-one million, three hundred forty thousand, three hundred sixty-seven".