21601367 has 2 divisors, whose sum is σ = 21601368. Its totient is φ = 21601366.

The previous prime is 21601343. The next prime is 21601397. The reversal of 21601367 is 76310612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21601367 - 2¹⁰ = 21600343 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21601337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10800683 + 10800684.

It is an arithmetic number, because the mean of its divisors is an integer number (10800684).

Almost surely, 2^21601367 is an apocalyptic number.

21601367 is a deficient number, since it is larger than the sum of its proper divisors (1).

21601367 is an equidigital number, since it uses as much as digits as its factorization.

21601367 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 21601367 is about 4647.7270789064. The cubic root of 21601367 is about 278.5012049409.

Adding to 21601367 its reverse (76310612), we get a palindrome (97911979).

The spelling of 21601367 in words is "twenty-one million, six hundred one thousand, three hundred sixty-seven".