21694367 has 2 divisors, whose sum is σ = 21694368. Its totient is φ = 21694366.

The previous prime is 21694303. The next prime is 21694381. The reversal of 21694367 is 76349612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21694367 - 2⁶ = 21694303 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 21694367.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21697367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10847183 + 10847184.

It is an arithmetic number, because the mean of its divisors is an integer number (10847184).

Almost surely, 2^21694367 is an apocalyptic number.

21694367 is a deficient number, since it is larger than the sum of its proper divisors (1).

21694367 is an equidigital number, since it uses as much as digits as its factorization.

21694367 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 38.

The square root of 21694367 is about 4657.7212239463. The cubic root of 21694367 is about 278.9003082459.

The spelling of 21694367 in words is "twenty-one million, six hundred ninety-four thousand, three hundred sixty-seven".