21958367 has 2 divisors, whose sum is σ = 21958368. Its totient is φ = 21958366.

The previous prime is 21958361. The next prime is 21958369. The reversal of 21958367 is 76385912.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21958367 - 2⁶ = 21958303 is a prime.

Together with 21958369, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21958361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10979183 + 10979184.

It is an arithmetic number, because the mean of its divisors is an integer number (10979184).

Almost surely, 2^21958367 is an apocalyptic number.

21958367 is a deficient number, since it is larger than the sum of its proper divisors (1).

21958367 is an equidigital number, since it uses as much as digits as its factorization.

21958367 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 21958367 is about 4685.9755654506. The cubic root of 21958367 is about 280.0270679615.

The spelling of 21958367 in words is "twenty-one million, nine hundred fifty-eight thousand, three hundred sixty-seven".